add a comparison of classic and modern polymorphism #10
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WalkthroughThe changes introduce enhancements to a C++ polymorphism project, including a new job step in the GitHub Actions workflow for building and testing with Debug configurations. A detailed README is added, explaining classic and modern polymorphism approaches, along with unit testing instructions. New header files define an interface and its implementation, while a new CMake configuration for the test directory specifies dependencies and executable targets for unit tests using the Boost UT framework. Additionally, a new configuration file for CodeRabbit integration is created. Changes
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Actionable comments posted: 5
🧹 Outside diff range and nitpick comments (25)
polymorphism/src/consume_class_that_adheres_to_concept.cpp (2)
1-3: Consider using project-relative paths for includes.The include statement on line 3 uses a relative path
<../src/consume_class_that_adheres_to_concept.ipp>. It's generally better to use project-relative paths for better maintainability and to avoid potential issues with different build environments.Consider changing the include to use a project-relative path, for example:
-#include <../src/consume_class_that_adheres_to_concept.ipp> +#include <polymorphism/consume_class_that_adheres_to_concept.ipp>Make sure to update your build configuration to include the appropriate include directories if necessary.
7-8: Fix typo and enhance comment for explicit template instantiation.There's a typo in the comment, and it could benefit from more context.
Consider updating the comment as follows:
-// explicit template instatiation +// Explicit template instantiation for the consume function +// This ensures that the template is instantiated for the Impl type, +// which adheres to the required concept. template std::string consume<Impl>(Impl&);This provides more information about the purpose and context of the explicit instantiation.
polymorphism/src/consume_class_with_interface.cpp (1)
5-10: LGTM with suggestions: Consider addingconstand error handling.The
consumefunction effectively demonstrates the use of theISuperCoolFeaturesinterface, which is great for showcasing classic polymorphism. A few suggestions for improvement:
Consider marking the parameter as
constsince the function doesn't modify it:std::string consume(const ISuperCoolFeatures& f)It might be beneficial to add error handling for potential exceptions thrown by the interface methods.
The use of "42" as the answer is a nice touch, referencing "The Hitchhiker's Guide to the Galaxy".
Would you like me to provide an example of how to implement error handling in this function?
polymorphism/include/polymorphism/consume_class_with_interface.hpp (1)
8-8: LGTM: Function declaration looks good. Ensure<string>is included in the implementation.The
consumefunction declaration is correct and uses a reference parameter, which is appropriate for polymorphic behavior.Make sure to include
<string>in the implementation file (.cpp) where this function is defined, asstd::stringis used as the return type.polymorphism/src/consume_class_that_adheres_to_concept.ipp (1)
9-13: Consider enhancing error handling and flexibility.The implementation looks functional but could benefit from some improvements:
- Error handling: Consider adding try-catch blocks to handle potential exceptions from
f.set()orf.coolFeature().- Flexibility: The hardcoded "42" might be better as a parameter or a configurable constant.
- Documentation: Adding a brief comment explaining the significance of "42" in this context would improve readability.
Here's a suggested improvement:
std::string consume(has_super_cool_features auto& f, const std::string& answer = "42") { try { f.set(answer); return "The answer to all questions is " + f.coolFeature(); } catch (const std::exception& e) { // Log the error or handle it appropriately return "An error occurred: " + std::string(e.what()); } }This version adds error handling and makes the "answer" configurable.
polymorphism/include/polymorphism/consume_class_that_adheres_to_concept.hpp (1)
8-9: LGTM with suggestions: Function declaration uses modern C++ concepts correctly.The function declaration effectively uses C++20 concepts syntax. However, consider the following suggestions:
- Enhance the comment to provide more context about the function's purpose and usage.
- Explicitly include the
<string>header to ensurestd::stringis properly defined.Consider applying these changes:
+#include <string> + namespace modern { -// declaration with concept constraint +// Consumes an object that adheres to the has_super_cool_features concept +// and returns a string representation or description of the object. std::string consume(has_super_cool_features auto& s);polymorphism/include/polymorphism/has_super_cool_features.hpp (1)
8-13: LGTM: Well-defined concept, but consider a more formal name.The concept is well-defined and correctly implements the required constraints. The use of
std::convertible_toandstd::same_asis appropriate for type checking. However, consider using a more formal name for the concept in production code, such asHasFeatureInterfaceorFeatureProvider.polymorphism/include/polymorphism/i_super_cool_features.hpp (3)
6-6: LGTM: Appropriate use of namespace.The
classicnamespace is used, which helps organize the code and avoid naming conflicts. This naming also suggests a comparison with modern C++ approaches.Consider adding a brief comment explaining the purpose of the
classicnamespace, especially if there's a correspondingmodernnamespace elsewhere in the project.
8-9: LGTM: Clear interface declaration with basic documentation.The interface is well-named following the 'I' prefix convention, and a brief documentation comment is provided.
Consider enhancing the documentation:
- Use a more descriptive name for the interface that reflects its specific purpose.
- Expand the documentation to include:
- The interface's purpose and use cases
- Any assumptions or constraints
- How it fits into the broader system architecture
- If using Doxygen, consider adding
@classand@brieftags for better documentation generation.
11-12: LGTM: Properly declared pure virtual functions.The pure virtual functions are correctly declared, with
coolFeature()appropriately marked asconst.Consider the following improvements:
- For
set(), pass the string parameter by const reference to avoid unnecessary copying:virtual void set(const std::string& s) = 0;- Add comments describing the purpose and behavior of each method.
- If applicable, use
[[nodiscard]]attribute forcoolFeature()to ensure the return value is used:[[nodiscard]] virtual std::string coolFeature() const = 0;polymorphism/src/main.cpp (4)
6-6: Consider revising the comment about iostream.While
<iostream>is indeed an older part of the C++ standard library, referring to it as "the legacy way to print stuff" might be misleading. It's still widely used and is part of the C++ standard. Consider removing the comment or rephrasing it to avoid potential confusion.
10-13: Consider using std::cout for regular output.While the classic polymorphism demonstration is correct, it's using
std::cerrfor output. Typically,std::cerris reserved for error messages. For regular program output, it's more conventional to usestd::cout.Consider changing:
- std::cerr << classic::consume(i) << '\n'; + std::cout << classic::consume(i) << '\n';
15-18: Correct modern polymorphism demonstration, but consider using std::cout.The modern polymorphism demonstration is implemented correctly. However, as with the classic demonstration, it's using
std::cerrfor output. For consistency and conventional use, consider usingstd::coutfor regular program output.Consider changing:
- std::cerr << modern::consume(i) << '\n'; + std::cout << modern::consume(i) << '\n';
20-20: Good use of EXIT_SUCCESS, but include .Using
EXIT_SUCCESSis a good practice for indicating successful program termination. However,EXIT_SUCCESSis defined in the<cstdlib>header, which is not included in this file.Add the following include at the beginning of the file:
#include <cstdlib>polymorphism/include/polymorphism/impl_with_interface.hpp (1)
11-22: LGTM: Class implementation is correct and efficient.The
Implclass correctly implements theISuperCoolFeaturesinterface:
coolFeature()is properly implemented as a const method.set(std::string s)efficiently usesstd::move.- Good use of C++11 default member initializer for
s_.Minor suggestion: Consider using
explicitfor the single-parameter constructor (if one is added in the future) to prevent implicit conversions.polymorphism/include/polymorphism/impl_without_interface.hpp (3)
8-10: Consider using a more descriptive class name.While the
modernnamespace is appropriately used, the class nameImplis quite generic. A more descriptive name that reflects the class's purpose or functionality would improve code readability and maintainability.For example, if this class implements a specific feature or concept, consider naming it accordingly, such as
CoolFeatureImplorSuperCoolFeaturesImpl.
12-12: Good use of default member initializer, but consider a more meaningful default value.The use of a default member initializer for
s_is a good C++11 practice. The naming convention for private members (trailing underscore) is also followed correctly.However, the default value
"<default value>"might not be meaningful in a real-world scenario. Consider using a more descriptive or domain-specific default value, or if no sensible default exists, you might want to require explicit initialization through a constructor.
22-23: Good use of static_assert, but consider adding documentation.The use of
static_assertto verify that theImplclass adheres to thehas_super_cool_featuresconcept is an excellent practice. This ensures interface compliance at compile-time, which is a key advantage of the modern C++ approach to polymorphism.However, it would be helpful to add a brief comment explaining what the
has_super_cool_featuresconcept requires. This would provide valuable context for developers working with or maintaining this code.polymorphism/test/CMakeLists.txt (2)
1-2: Consider using a lower CMake version requirement.The current minimum required CMake version (3.29) is very recent. This high version requirement might limit the portability of the project, as not all systems may have this version available yet.
Consider lowering the required version if the project doesn't specifically need features from CMake 3.29. For example, you could try version 3.20 or 3.22, which are more widely available while still providing modern CMake features.
22-25: Test registration looks good, consider additional configuration.The test registration is correct and straightforward. However, you might want to consider adding more configuration options for better test output and integration with CI systems.
Consider adding the following options to enhance your test configuration:
add_test( NAME test_consume COMMAND test_consume ) set_tests_properties(test_consume PROPERTIES FAIL_REGULAR_EXPRESSION "FAILED;ERROR" PASS_REGULAR_EXPRESSION "All tests passed" TIMEOUT 5 # Adjust as needed )These additional properties help in automatically determining test success/failure and prevent tests from running indefinitely.
polymorphism/test/test_consume.cpp (1)
27-45: LGTM: Well-structured BDD-style test with a minor suggestion.This BDD-style test case is well-structured and provides a clear, readable description of the modern implementation's behavior. It effectively covers:
- The initial state
- The behavior of the
consumefunction- The side effect on the
implobjectThe use of nested contexts (given-when-then) allows for a more detailed and expressive test, which is excellent for documenting expected behavior.
For consistency with the previous tests, consider adding an expectation for the initial state of
impl.coolFeature()immediately after creating theimplobject:given("I have a an implementation that adheres to a concept") = [] { modern::Impl impl; + expect("<default value>"s == impl.coolFeature()); when("I pass it to a function that expects an argument that fulfils the constraints") = [&] {This addition would make the test even more comprehensive and consistent with the previous test cases.
.github/workflows/build_examples.yml (1)
48-50: Address TODO comments for potential workflow improvements.There are two TODO comments at the end of the file suggesting potential improvements to the workflow:
- Check https://github.com/marketplace/actions/cmake-swiss-army-knife
- Check https://github.com/actions/starter-workflows/blob/9f1db534549e072c20d5d1a79e0a4ff45a674caf/ci/cmake-multi-platform.yml#L20
These resources could help streamline and improve the current workflow. Consider reviewing them and implementing any relevant improvements.
Would you like assistance in evaluating these resources and proposing specific improvements to the workflow?
polymorphism/README.md (3)
36-48: Comprehensive test instructions with room for improvementThe test instructions are clear and include helpful flags like
--output-on-failurefor debugging. This is great for users who want to run and verify the tests.Consider adding a brief explanation of what the tests cover. This would give users a better understanding of what's being tested and why it's important.
50-194: Excellent code explanations with minor improvements neededThe code explanations for both classic and modern approaches to polymorphism are thorough and well-structured. The inclusion of code snippets and discussions on advantages and trade-offs is particularly valuable. The section on testing with the µt framework is also informative.
There are a few minor typographical and grammatical issues that could be addressed to improve readability:
- Line 54: Add a comma after "In this example".
- Line 86: Add a comma after "ISuperCoolFeatures".
- Line 107: Change "can passed" to "can be passed".
- Line 109: Add a comma after "point of view".
- Line 111: Remove the repeated "a" in "as a a concept".
- Line 134: Add a comma after "In this approach".
- Line 162: Add a comma after "In this example".
- Line 175: Add a comma after "In this example".
These small changes will enhance the overall quality of the document.
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[typographical] ~54-~54: It appears that a comma is missing.
Context: ...ementation (publicly) inherits. In this example we have defined such an abstract class:...(DURING_THAT_TIME_COMMA)
[misspelling] ~65-~65: A “base” is a flat surface. The correct phrase is “regular basis” (basis = a metaphorical base).
Context: ...r function body (which is possible in a regular base class), the member functions of an abst...(BASE_BASIS)
[uncategorized] ~86-~86: Possible missing comma found.
Context: ...ace typeISuperCoolFeatures. In our example we define a function which has one argu...(AI_HYDRA_LEO_MISSING_COMMA)
[grammar] ~107-~107: Did you mean “be passed”?
Context: ...cts of completely unrelated classes can passed as arguments to a member function (aka ...(WILL_BASED_ON)
[uncategorized] ~109-~109: Possible missing comma found.
Context: ...ined. From a code structuring point of view this means that the cohesion between di...(AI_HYDRA_LEO_MISSING_COMMA)
[typographical] ~111-~111: It appears that a comma is missing.
Context: ...parts of the code is reduced. In this example we have defined such an interface speci...(DURING_THAT_TIME_COMMA)
[duplication] ~111-~111: Possible typo: you repeated a word
Context: ...ined such an interface specification as a a concept: ```c++ template ...(ENGLISH_WORD_REPEAT_RULE)
[typographical] ~134-~134: It appears that a comma is missing.
Context: ...c++ Impl i; consume(i);In this approach our implementation is defined **without...(DURING_THAT_TIME_COMMA)
[typographical] ~162-~162: It appears that a comma is missing.
Context: ...le at the point of usage. In this example we use explicit instantiation to show t...(DURING_THAT_TIME_COMMA)
[typographical] ~175-~175: It appears that a comma is missing.
Context: ... longer required. ## Testing In this example we use [µt](https://github.com/boost-ex...(DURING_THAT_TIME_COMMA)
10-10: Maintain consistent heading styleFor better consistency throughout the document, consider changing the heading style on line 10 to match the other headings in the README. Use the ATX style (with
#symbols) without closing#symbols.Change:
##to:
## Build InstructionsThis will improve the overall structure and readability of the document.
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10-10: Expected: atx; Actual: atx_closed
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📜 Review details
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Review profile: CHILL
📒 Files selected for processing (15)
- .github/workflows/build_examples.yml (1 hunks)
- polymorphism/CMakeLists.txt (1 hunks)
- polymorphism/README.md (1 hunks)
- polymorphism/include/polymorphism/consume_class_that_adheres_to_concept.hpp (1 hunks)
- polymorphism/include/polymorphism/consume_class_with_interface.hpp (1 hunks)
- polymorphism/include/polymorphism/has_super_cool_features.hpp (1 hunks)
- polymorphism/include/polymorphism/i_super_cool_features.hpp (1 hunks)
- polymorphism/include/polymorphism/impl_with_interface.hpp (1 hunks)
- polymorphism/include/polymorphism/impl_without_interface.hpp (1 hunks)
- polymorphism/src/consume_class_that_adheres_to_concept.cpp (1 hunks)
- polymorphism/src/consume_class_that_adheres_to_concept.ipp (1 hunks)
- polymorphism/src/consume_class_with_interface.cpp (1 hunks)
- polymorphism/src/main.cpp (1 hunks)
- polymorphism/test/CMakeLists.txt (1 hunks)
- polymorphism/test/test_consume.cpp (1 hunks)
✅ Files skipped from review due to trivial changes (1)
- polymorphism/CMakeLists.txt
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polymorphism/README.md
[typographical] ~54-~54: It appears that a comma is missing.
Context: ...ementation (publicly) inherits. In this example we have defined such an abstract class:...(DURING_THAT_TIME_COMMA)
[misspelling] ~65-~65: A “base” is a flat surface. The correct phrase is “regular basis” (basis = a metaphorical base).
Context: ...r function body (which is possible in a regular base class), the member functions of an abst...(BASE_BASIS)
[uncategorized] ~86-~86: Possible missing comma found.
Context: ...ace typeISuperCoolFeatures. In our example we define a function which has one argu...(AI_HYDRA_LEO_MISSING_COMMA)
[grammar] ~107-~107: Did you mean “be passed”?
Context: ...cts of completely unrelated classes can passed as arguments to a member function (aka ...(WILL_BASED_ON)
[uncategorized] ~109-~109: Possible missing comma found.
Context: ...ined. From a code structuring point of view this means that the cohesion between di...(AI_HYDRA_LEO_MISSING_COMMA)
[typographical] ~111-~111: It appears that a comma is missing.
Context: ...parts of the code is reduced. In this example we have defined such an interface speci...(DURING_THAT_TIME_COMMA)
[duplication] ~111-~111: Possible typo: you repeated a word
Context: ...ined such an interface specification as a a concept: ```c++ template ...(ENGLISH_WORD_REPEAT_RULE)
[typographical] ~134-~134: It appears that a comma is missing.
Context: ...c++ Impl i; consume(i);In this approach our implementation is defined **without...(DURING_THAT_TIME_COMMA)
[typographical] ~162-~162: It appears that a comma is missing.
Context: ...le at the point of usage. In this example we use explicit instantiation to show t...(DURING_THAT_TIME_COMMA)
[typographical] ~175-~175: It appears that a comma is missing.
Context: ... longer required. ## Testing In this example we use [µt](https://github.com/boost-ex...(DURING_THAT_TIME_COMMA)
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polymorphism/README.md
10-10: Expected: atx; Actual: atx_closed
Heading style(MD003, heading-style)
28-28: Punctuation: ':'
Trailing punctuation in heading(MD026, no-trailing-punctuation)
🔇 Additional comments (32)
polymorphism/src/consume_class_that_adheres_to_concept.cpp (1)
1-10: LGTM! The overall structure and purpose of the file are sound.The file successfully sets up the explicit template instantiation for the
consumefunction with theImpltype. This is a good practice for optimizing compile times and ensuring specific instantiations are available. The use of namespaces and the overall organization of the code are commendable.polymorphism/src/consume_class_with_interface.cpp (1)
1-3: LGTM: File structure and include statement are appropriate.The include statement and namespace usage are consistent with the project's structure and objectives. The
classicnamespace effectively separates this implementation from potential modern approaches.polymorphism/include/polymorphism/consume_class_with_interface.hpp (3)
1-2: LGTM: Include guards are correctly implemented.The include guards are properly set up using the macro
CONSUME_CLASS_WITH_INTERFACE_HPP. This prevents multiple inclusions of the header file, which is a good practice.Also applies to: 12-12
6-6: LGTM: Appropriate use of namespace.The
classicnamespace is correctly declared and closed. This helps organize the code and prevent naming conflicts, especially if there are modern counterparts to these classic implementations.Also applies to: 10-10
4-4: LGTM: Header inclusion looks correct. Verify the included file exists.The inclusion of
<polymorphism/i_super_cool_features.hpp>is appropriate as it likely contains the definition of theISuperCoolFeaturesinterface used in this file.To ensure the included file exists, run the following command:
✅ Verification successful
Verified: The included header file
i_super_cool_features.hppexists as specified.🏁 Scripts executed
The following scripts were executed for the analysis:
Script:
#!/bin/bash # Verify the existence of the included header file fd -t f "i_super_cool_features.hpp" polymorphism/includeLength of output: 116
polymorphism/src/consume_class_that_adheres_to_concept.ipp (3)
1-5: LGTM: File structure and includes are appropriate.The file structure is well-organized with proper includes and namespace usage. The inclusion of the corresponding header file and the
<string>header is appropriate for the implementation.Also applies to: 15-15
7-8: LGTM: Excellent use of concepts for type constraints.The function declaration effectively uses the
has_super_cool_featuresconcept constraint withauto&. This modern C++ approach ensures type safety at compile-time while allowing for generic programming.
1-15: Overall, well-implemented modern C++ approach with room for minor enhancements.This implementation effectively demonstrates the use of concepts in modern C++, aligning well with the project's objectives. The code is concise and type-safe. Consider the suggested improvements for error handling and flexibility to further enhance the robustness of the implementation.
polymorphism/include/polymorphism/consume_class_that_adheres_to_concept.hpp (3)
1-2: LGTM: Include guards are correctly implemented.The include guards are properly set up, using a specific and appropriate macro name for this file.
Also applies to: 13-13
4-4: LGTM: Appropriate include statement.The include statement is correctly placed and likely provides the necessary
has_super_cool_featuresconcept definition.
6-6: LGTM: Appropriate namespace usage.The
modernnamespace is correctly opened and closed, providing a clear scope for the modern C++ approach using concepts.Also applies to: 11-11
polymorphism/include/polymorphism/has_super_cool_features.hpp (5)
1-5: LGTM: Header guards and includes are properly set up.The header guards and includes are correctly implemented. The use of
<string>is appropriate for the concept definition.
6-7: LGTM: Appropriate namespace usage.The use of the
modernnamespace is a good practice and appropriately named for the context of the concept.
15-15: LGTM: Proper namespace closing.The
modernnamespace is correctly closed, and the comment indicating which namespace is being closed is a good practice for readability.
17-17: LGTM: Proper header guard closing.The header guard is correctly closed, and the comment indicating which macro is being closed is a good practice for readability.
1-17: Overall: Well-implemented concept demonstrating modern C++ features.This file successfully introduces a C++ concept that aligns well with the PR objective of adding the first concepts example. The implementation is correct, follows good practices, and demonstrates the use of modern C++ features such as concepts and type constraints. The only suggestion for improvement is to consider a more formal name for the concept in production code.
Great job on implementing this example of modern C++ polymorphism using concepts!
polymorphism/include/polymorphism/i_super_cool_features.hpp (4)
1-5: LGTM: Proper include guards and necessary header inclusion.The include guards are correctly implemented, and the
<string>header is included as required for usingstd::stringin the interface.
13-13: LGTM: Correctly declared virtual destructor.The virtual destructor is properly declared as default, which is essential for base classes to ensure proper cleanup of derived classes.
16-16: LGTM: Proper namespace closing with comment.The
classicnamespace is correctly closed, and the closing comment enhances readability.
1-18: Overall, well-structured interface with room for minor improvements.The
ISuperCoolFeaturesinterface is well-implemented, demonstrating classic C++ polymorphism. The use of include guards, namespaces, and virtual functions is correct. To further improve the code:
- Enhance documentation for the interface and its methods.
- Consider passing the string parameter in
set()by const reference.- Use more specific naming for the interface if possible.
- Add the
[[nodiscard]]attribute tocoolFeature()if applicable.These changes will improve code efficiency, clarity, and maintainability.
polymorphism/src/main.cpp (2)
8-9: Well-structured main function.The main function is well-organized with separate scopes for demonstrating classic and modern polymorphism approaches. This structure ensures clear separation of concerns and proper resource management.
Also applies to: 20-21
1-21: Overall, well-implemented demonstration of polymorphism concepts.This main.cpp file effectively demonstrates both classic and modern approaches to polymorphism. The code is well-structured, with clear separation between the two approaches. The minor suggestions provided (using std::cout, including ) will further improve the code quality and adherence to best practices.
Great job on implementing this educational example of polymorphism in C++!
polymorphism/include/polymorphism/impl_with_interface.hpp (1)
1-9: LGTM: File structure and includes are well-organized.The file structure is clean and follows best practices:
- Proper include guards are used.
- Necessary headers are included.
- The implementation is correctly placed in the
classicnamespace.Also applies to: 24-26
polymorphism/include/polymorphism/impl_without_interface.hpp (3)
1-7: LGTM: Proper header guards and includes.The header guards are correctly implemented, and the necessary includes are present. The local include
<polymorphism/has_super_cool_features.hpp>suggests a dependency on a concept definition, which aligns with the modern C++ approach to polymorphism.
15-19: LGTM: Well-implemented public methods.The public methods are implemented correctly:
coolFeature()is appropriately marked asconst.set(std::string s)efficiently usesstd::movefor string handling.The simplicity of these methods is suitable for this small class. The absence of an explicit constructor seems intentional, allowing the default member initializer to handle object creation.
1-27: Overall, well-implemented modern C++ approach to polymorphism.This file successfully demonstrates a modern C++ approach to polymorphism using concepts instead of traditional interfaces. The code is well-structured, uses appropriate C++11 features, and follows good C++ practices.
Key strengths:
- Proper use of header guards and includes
- Efficient implementation of methods
- Use of static_assert for compile-time interface checking
Minor suggestions for improvement:
- Consider a more descriptive class name
- Use a more meaningful default value for the private member
- Add brief documentation for the
has_super_cool_featuresconceptThese changes would further enhance the code's readability and maintainability.
polymorphism/test/test_consume.cpp (4)
1-12: LGTM: Well-structured imports and namespace usage.The imports and namespace usage are well-organized. Using namespace aliases for Boost UT and std::string_literals is a good practice to avoid polluting the global namespace while maintaining readability.
14-18: LGTM: Comprehensive test for classic interface.This test case effectively covers the basic functionality of the classic implementation. It verifies both the initial state (
coolFeature()returns "") and the behavior after callingclassic::consume. The expectations are clear and concise.
20-25: LGTM: Comprehensive test for modern interface with state change verification.This test case effectively covers the functionality of the modern implementation. It verifies:
- The initial state (
coolFeature()returns "")- The behavior of
modern::consume- The state change after calling
consume(coolFeature()now returns "42")The inclusion of the state change verification is particularly good, as it highlights a key difference between the classic and modern implementations.
1-46: Excellent test coverage and structure for polymorphism implementations.This test file provides comprehensive coverage for both classic and modern polymorphism implementations. The use of different testing styles (simple unit tests and BDD) enhances readability and thoroughness. Key strengths include:
- Clear separation of classic and modern interface tests
- Verification of initial states, consume function behavior, and state changes
- Well-structured BDD-style test for detailed behavior description
The test suite effectively validates the functionality of the polymorphism implementations and serves as good documentation for expected behavior.
polymorphism/README.md (2)
1-10: Great introduction and summary!The summary effectively introduces the two approaches to polymorphism (classic and modern) and mentions the use of the ut testing framework. This provides a clear overview of what the reader can expect from this example.
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12-34: Clear and comprehensive build instructionsThe build instructions are well-structured and easy to follow. They cover both release and debug builds using CMake, which is excellent. This section will be very helpful for users trying to build the project.
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Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>
…rose/cplusplus-primer into add-first-concepts-example
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Actionable comments posted: 1
🧹 Outside diff range and nitpick comments (5)
.github/workflows/build_examples.yml (1)
56-57: Address TODO comments for potential workflow improvements.There are two TODO comments at the end of the file suggesting to check out potentially useful GitHub Actions:
- CMAKE Swiss Army Knife
- CMake Multi-Platform Starter Workflow
Consider reviewing these actions and incorporating them if they can improve your workflow. Once done, remove the TODO comments.
polymorphism/README.md (4)
10-32: LGTM: Clear build instructions with a minor suggestionThe build instructions are well-structured and easy to follow. The inclusion of both release and debug build commands is helpful.
Consider removing the extra space at the end of line 19 for consistency:
-For debug builds use +For debug builds use🧰 Tools
🪛 LanguageTool
[uncategorized] ~19-~19: Possible missing comma found.
Context: ...ymorphism -S polymorphismFor debug builds usebash cmake -D CMAKE_BUILD_TY...(AI_HYDRA_LEO_MISSING_COMMA)
48-97: LGTM: Comprehensive explanation of the classic approach with a minor correctionThe explanation of the classic approach to polymorphism is thorough and well-illustrated with code examples. It provides a good foundation for understanding abstract base classes and their implementation.
There's a minor typo on line 82. Please correct it as follows:
-A variable (aka instatiation) of type `Impl` can be passed as argument to any function that expects an argument of its interface type `ISuperCoolFeatures`. +A variable (aka instantiation) of type `Impl` can be passed as argument to any function that expects an argument of its interface type `ISuperCoolFeatures`.🧰 Tools
🪛 LanguageTool
[misspelling] ~63-~63: A “base” is a flat surface. The correct phrase is “regular basis” (basis = a metaphorical base).
Context: ...r function body (which is possible in a regular base class), the member functions of an abst...(BASE_BASIS)
99-171: LGTM: Excellent explanation of the modern approach with a minor correctionThe explanation of the modern approach to polymorphism using concepts is comprehensive and well-illustrated with code examples. The discussion of advantages and trade-offs provides valuable context for understanding when to use this approach.
There's a minor typo on line 166. Please correct it as follows:
-// explicit template instatiation +// explicit template instantiation🧰 Tools
🪛 LanguageTool
[typographical] ~109-~109: It appears that a comma is missing.
Context: ...parts of the code is reduced. In this example we have defined such an interface speci...(DURING_THAT_TIME_COMMA)
109-109: Consider adding a comma for improved readabilityTo enhance readability, consider adding a comma after "In this example" on line 109:
-In this example we have defined such an interface specification as a concept: +In this example, we have defined such an interface specification as a concept:🧰 Tools
🪛 LanguageTool
[typographical] ~109-~109: It appears that a comma is missing.
Context: ...parts of the code is reduced. In this example we have defined such an interface speci...(DURING_THAT_TIME_COMMA)
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Review profile: CHILL
📒 Files selected for processing (5)
- .github/workflows/build_examples.yml (3 hunks)
- polymorphism/README.md (1 hunks)
- polymorphism/include/polymorphism/i_super_cool_features.hpp (1 hunks)
- polymorphism/include/polymorphism/impl_with_interface.hpp (1 hunks)
- polymorphism/test/CMakeLists.txt (1 hunks)
🚧 Files skipped from review as they are similar to previous changes (3)
- polymorphism/include/polymorphism/i_super_cool_features.hpp
- polymorphism/include/polymorphism/impl_with_interface.hpp
- polymorphism/test/CMakeLists.txt
🧰 Additional context used
🪛 LanguageTool
polymorphism/README.md
[uncategorized] ~19-~19: Possible missing comma found.
Context: ...ymorphism -S polymorphismFor debug builds usebash cmake -D CMAKE_BUILD_TY...(AI_HYDRA_LEO_MISSING_COMMA)
[misspelling] ~63-~63: A “base” is a flat surface. The correct phrase is “regular basis” (basis = a metaphorical base).
Context: ...r function body (which is possible in a regular base class), the member functions of an abst...(BASE_BASIS)
[typographical] ~109-~109: It appears that a comma is missing.
Context: ...parts of the code is reduced. In this example we have defined such an interface speci...(DURING_THAT_TIME_COMMA)
🔇 Additional comments (7)
.github/workflows/build_examples.yml (3)
48-49: LGTM: Configuration step for polymorphism added correctly.The new configuration step for the polymorphism project follows the suggested structure and is consistent with the existing workflow.
51-52: LGTM: Build step for polymorphism added correctly.The new build step for the polymorphism project follows the suggested structure and is consistent with the existing workflow.
54-55: LGTM: Test step for polymorphism added correctly.The new test step for the polymorphism project follows the suggested structure and is consistent with the existing workflow.
polymorphism/README.md (4)
1-8: LGTM: Concise and informative summaryThe summary effectively introduces the two approaches to polymorphism and mentions the unit testing framework. The inclusion of relevant links is helpful for readers seeking more information.
34-46: LGTM: Comprehensive test instructionsThe test instructions are clear and provide the necessary commands for building and running tests. The use of the
VERBOSE=1flag for building and--output-on-failureflag for running tests are helpful additions for debugging and understanding test results.
172-192: LGTM: Clear explanation of testing setupThe Testing section provides a concise explanation of how the µt (ut) testing framework is integrated into the project. The inclusion of CMake commands and a link to further documentation is helpful for users implementing and understanding the testing setup.
1-192: Excellent README with comprehensive explanations and instructionsThis README provides a thorough and well-structured explanation of both classic and modern approaches to polymorphism in C++. The build and test instructions are clear, and the code examples effectively illustrate the concepts. The minor typos and formatting issues identified earlier do not detract from the overall high quality of the document.
Great job on creating such an informative and helpful README!
🧰 Tools
🪛 LanguageTool
[uncategorized] ~19-~19: Possible missing comma found.
Context: ...ymorphism -S polymorphismFor debug builds usebash cmake -D CMAKE_BUILD_TY...(AI_HYDRA_LEO_MISSING_COMMA)
[misspelling] ~63-~63: A “base” is a flat surface. The correct phrase is “regular basis” (basis = a metaphorical base).
Context: ...r function body (which is possible in a regular base class), the member functions of an abst...(BASE_BASIS)
[typographical] ~109-~109: It appears that a comma is missing.
Context: ...parts of the code is reduced. In this example we have defined such an interface speci...(DURING_THAT_TIME_COMMA)
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Actionable comments posted: 13
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📒 Files selected for processing (4)
- polymorphism/CMakeLists.txt (1 hunks)
- polymorphism/README.md (1 hunks)
- polymorphism/src/consume_class_that_adheres_to_concept.cpp (1 hunks)
- polymorphism/test/CMakeLists.txt (1 hunks)
🧰 Additional context used
📓 Learnings (1)
polymorphism/test/CMakeLists.txt (1)
Learnt from: daixtrose PR: daixtrose/cplusplus-primer#10 File: polymorphism/test/CMakeLists.txt:3-10 Timestamp: 2024-10-16T14:58:34.289Z Learning: In `polymorphism/test/CMakeLists.txt`, it's acceptable to fetch Boost UT from the `master` branch using `FetchContent` to use the latest version.
🪛 LanguageTool
polymorphism/README.md
[misspelling] ~63-~63: A “base” is a flat surface. The correct phrase is “regular basis” (basis = a metaphorical base).
Context: ...r function body (which is possible in a regular base class), the member functions of an abst...(BASE_BASIS)
[uncategorized] ~84-~84: Possible missing comma found.
Context: ...ace typeISuperCoolFeatures. In our example we define a function which has one argu...(AI_HYDRA_LEO_MISSING_COMMA)
🪛 Markdownlint
polymorphism/README.md
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🔇 Additional comments (8)
polymorphism/src/consume_class_that_adheres_to_concept.cpp (2)
4-4: LGTM! Appropriate use of namespace.The
modernnamespace is well-chosen for demonstrating modern C++ concepts. The namespace declaration follows standard C++ practices.Also applies to: 9-9
1-9: Overall, well-structured and purposeful implementation.This file effectively demonstrates the use of modern C++ concepts, particularly with templates and explicit instantiation. It's a concise and focused implementation that fits well within a project showcasing polymorphism techniques.
To further enhance the code:
- Consider adding include guards to the
.ippfile if not already present.- Fix the typo in the comment as mentioned earlier.
These minor improvements will make the code even more robust and professional.
polymorphism/CMakeLists.txt (2)
5-5: LGTM: Well-defined testing option.The testing option is well-defined with a clear name and a sensible default value. Using
${PROJECT_IS_TOP_LEVEL}ensures that testing is enabled by default when the project is the top-level project, which is a good practice for subproject compatibility.
13-13: Consider the implications of using C++23.While using C++23 is forward-thinking, it might limit compiler compatibility, especially with older systems or compilers. Unless you specifically need C++23 features, consider using a more widely supported standard like C++17 or C++20.
To check compiler support for C++23 in your CI environment, you can run:
polymorphism/test/CMakeLists.txt (3)
1-10: Consider the implications of using CMake 3.29.The minimum CMake version is set to 3.29, which is a very recent version. This might limit compatibility with systems that have older CMake versions installed. Consider if this high version is necessary for your project, or if a lower version would suffice while maintaining broader compatibility.
Regarding the Boost UT fetching:
As per your previous feedback, fetching Boost UT from the master branch is acceptable in this context to use the latest version.
21-30: Executable target setup is well-structured.The
test_consumeexecutable is set up correctly:
- It uses the C++23 standard, consistent with the library.
- Appropriate include directories are set.
- It's properly linked with the
polymorphism_liblibrary.This setup follows good CMake practices for test executables.
1-35: Overall, the CMakeLists.txt file is well-structured and follows good practices.The file successfully sets up the library, executable, and test targets for the project. It uses modern CMake practices and C++23, showing a forward-thinking approach. The suggestions provided in the review are minor optimizations that can further enhance the configuration.
Key points:
- Consider the implications of requiring CMake 3.29.
- The library and executable setups are solid.
- The test configuration could benefit from additional parameters.
Great job on setting up this CMake configuration!
polymorphism/README.md (1)
34-46: Well-structured test instructions.The test instructions are clear, concise, and provide all necessary information for building and running tests. The use of the VERBOSE flag in the build command is a good practice for debugging purposes.
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@coderabbitai, please recheck the pull request and summarize your findings. |
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Tip For best results, initiate chat on the files or code changes. I have rechecked the pull request and here is a summary of my findings: Summary of Changes:
Findings:
Suggestions:
Conclusion: The pull request significantly enhances the repository by adding informative examples of polymorphism in C++. The combination of classic and modern approaches provides a comprehensive learning resource. Addressing the suggestions above will improve compatibility and maintainability. If you have any questions or need further assistance, feel free to ask. |
daixtrose
changed the title
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@coderabbitai, please recheck the pull request and summarize your findings. Please respect in your analysis that I want to use the latest versions of all build and configuration tools, especially for compilers, C++ versions, and CMake. |
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Tip For best results, initiate chat on the files or code changes. I have rechecked the pull request, respecting your preference to use the latest versions of build and configuration tools. Here is an updated summary of my findings: Summary of Changes:
Findings:
Suggestions:
Conclusion: The pull request significantly enhances the repository by adding informative examples of polymorphism in C++. The use of the latest versions of compilers, C++ standards, and build tools demonstrates a commitment to leveraging modern features and capabilities, providing a cutting-edge learning resource. Addressing the suggestions above will further improve the project. Thank you for clarifying your preference to use the latest versions of build tools. I've noted this for future reviews. (_/) (•_•) (💭) ✏️ Learnings added
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Actionable comments posted: 19
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📒 Files selected for processing (11)
- polymorphism/CMakeLists.txt (1 hunks)
- polymorphism/README.md (1 hunks)
- polymorphism/include/polymorphism/consume_class_that_adheres_to_concept.hpp (1 hunks)
- polymorphism/include/polymorphism/consume_class_with_interface.hpp (1 hunks)
- polymorphism/include/polymorphism/has_super_cool_features.hpp (1 hunks)
- polymorphism/include/polymorphism/i_super_cool_features.hpp (1 hunks)
- polymorphism/include/polymorphism/impl_with_interface.hpp (1 hunks)
- polymorphism/include/polymorphism/impl_without_interface.hpp (1 hunks)
- polymorphism/src/consume_class_that_adheres_to_concept.cpp (1 hunks)
- polymorphism/src/consume_class_that_adheres_to_concept.ipp (1 hunks)
- polymorphism/test/CMakeLists.txt (1 hunks)
🧰 Additional context used
📓 Learnings (2)
polymorphism/CMakeLists.txt (1)
Learnt from: daixtrose PR: daixtrose/cplusplus-primer#10 File: polymorphism/CMakeLists.txt:1-3 Timestamp: 2024-10-16T21:16:21.134Z Learning: For the project `polymorphism`, the user intentionally uses the latest and greatest C++ and CMake features.polymorphism/test/CMakeLists.txt (1)
Learnt from: daixtrose PR: daixtrose/cplusplus-primer#10 File: polymorphism/test/CMakeLists.txt:3-10 Timestamp: 2024-10-16T14:58:34.289Z Learning: In `polymorphism/test/CMakeLists.txt`, it's acceptable to fetch Boost UT from the `master` branch using `FetchContent` to use the latest version.
🪛 LanguageTool
polymorphism/README.md
[uncategorized] ~8-~8: Possible missing comma found.
Context: ... implementation inherits. 2. The modern approach using [concepts](https://en.cppreferenc...(AI_HYDRA_LEO_MISSING_COMMA)
[uncategorized] ~21-~21: Possible missing comma found.
Context: ...ymorphism -S polymorphismFor debug builds usebash cmake -D CMAKE_BUILD_TYPE=...(AI_HYDRA_LEO_MISSING_COMMA)
[uncategorized] ~174-~174: Use a comma before ‘and’ if it connects two independent clauses (unless they are closely connected and short).
Context: ...ason. It looks promising and lightweight and it was written by [Krzysztof Jusiak](ht...(COMMA_COMPOUND_SENTENCE)
🪛 Markdownlint
polymorphism/README.md
174-174: Expected: 0 or 2; Actual: 3
Trailing spaces(MD009, no-trailing-spaces)
20-20: null
Fenced code blocks should be surrounded by blank lines(MD031, blanks-around-fences)
🔇 Additional comments (32)
polymorphism/src/consume_class_that_adheres_to_concept.cpp (2)
1-2: LGTM! Include statements are appropriate.The include statements are correct and necessary for this file. The
.ippfile likely contains the implementation of theconsumefunction template, whileimpl_without_interface.hpppresumably defines theImplclass.
4-4: LGTM! Appropriate namespace usage.The use of the
modernnamespace is consistent with the file's purpose of demonstrating modern polymorphism techniques. It helps to organize the code and prevent naming conflicts.Also applies to: 9-9
polymorphism/include/polymorphism/consume_class_with_interface.hpp (3)
4-4: Include statement looks good.The inclusion of
i_super_cool_features.hppis appropriate as it's likely whereISuperCoolFeaturesis defined, which is used in theconsumefunction declaration.
6-6: Namespace usage is appropriate.The use of the
classicnamespace is good practice for organizing code and preventing naming conflicts. It also aligns well with the PR objective of comparing classic and modern polymorphism approaches.Also applies to: 10-10
8-8: Function declaration looks good, but verify string inclusion.The
consumefunction declaration is clear and appropriate for demonstrating polymorphism. The use of a reference parameter forISuperCoolFeaturesis correct for polymorphic behavior.Please ensure that
<string>is included, either in this file or ini_super_cool_features.hpp. Run the following script to verify:If neither file includes
<string>, consider adding#include <string>at the beginning of this file.✅ Verification successful
Function declaration verified and approved.
The
consumefunction declaration is clear and appropriate for demonstrating polymorphism. The use of a reference parameter forISuperCoolFeaturesis correct for polymorphic behavior. Additionally,<string>is included ini_super_cool_features.hpp, ensuring the return type is properly handled.🏁 Scripts executed
The following scripts were executed for the analysis:
Script:
#!/bin/bash # Description: Check if <string> is included in relevant files # Check this file echo "Checking consume_class_with_interface.hpp:" rg --type cpp '<string>' polymorphism/include/polymorphism/consume_class_with_interface.hpp # Check i_super_cool_features.hpp echo "Checking i_super_cool_features.hpp:" rg --type cpp '<string>' polymorphism/include/polymorphism/i_super_cool_features.hppLength of output: 374
polymorphism/include/polymorphism/consume_class_that_adheres_to_concept.hpp (2)
4-4: Include statement looks goodThe include statement for "polymorphism/has_super_cool_features.hpp" is correct and necessary for using the
has_super_cool_featuresconcept in the function declaration.
6-6: Namespace usage is appropriateThe use of the
modernnamespace is good practice and aligns well with the modern approach to polymorphism described in the PR objectives. The namespace is properly opened and closed.Also applies to: 11-11
polymorphism/include/polymorphism/has_super_cool_features.hpp (2)
4-4: Includes look goodThe inclusion of is appropriate and necessary for using std::string in the concept definition.
6-6: Namespace usage is appropriateThe use of the "modern" namespace is a good choice for encapsulating this modern C++ approach to polymorphism. It clearly separates this concept from potential classic implementations.
Also applies to: 15-15
polymorphism/src/consume_class_that_adheres_to_concept.ipp (2)
8-8: Appropriate namespace usage.The use of the
modernnamespace is well-suited for encapsulating this implementation of modern C++ features. It helps organize the code and prevent potential name conflicts.Also applies to: 18-18
1-20: Well-structured and consistent implementation file.The overall structure of this .ipp file is excellent. It follows a logical order and adheres to good C++ practices. The use of the .ipp extension for an inline implementation file is correct.
polymorphism/include/polymorphism/i_super_cool_features.hpp (3)
1-2: LGTM: Include guards are correctly implemented.The include guards use a descriptive and unique macro name that follows best practices, helping to prevent multiple inclusions and potential naming conflicts.
Also applies to: 18-18
4-4: LGTM: Necessary include statement present.The
<string>header is correctly included, which is required for thestd::stringusage in the interface methods.
6-6: LGTM: Appropriate namespace usage.The
classicnamespace is well-chosen for encapsulating the interface, reflecting its role in demonstrating classic polymorphism. This helps organize the code and prevent potential naming conflicts.Also applies to: 16-16
polymorphism/include/polymorphism/impl_with_interface.hpp (4)
1-8: LGTM: Include guards and includes are properly set up.The include guards follow good naming conventions, matching the file path. Necessary headers for the interface and string manipulation are included.
9-9: LGTM: Appropriate namespace usage.The use of the
classicnamespace is appropriate for encapsulating the traditional polymorphism implementation.
24-26: LGTM: Proper closure of namespace and include guard.The namespace is correctly closed with an appropriate comment, and the include guard is properly terminated.
1-26: Overall, excellent implementation of classic polymorphism.This file successfully demonstrates the classic polymorphism approach in C++ using inheritance. The code is well-structured, follows good C++ practices, and uses modern C++ features appropriately. The minor suggestions provided earlier will further enhance the code's clarity and flexibility.
Great job on implementing this example of classic polymorphism!
polymorphism/include/polymorphism/impl_without_interface.hpp (2)
8-20: Good use of namespace and modern C++ featuresThe code demonstrates good practices:
- Use of a namespace to avoid naming conflicts.
- Clean class structure.
- Utilization of C++11 default member initializer.
These choices contribute to more maintainable and modern C++ code.
Also applies to: 25-25
1-27: Overall, well-implemented modern C++ exampleThis file successfully demonstrates modern C++ polymorphism techniques without using traditional interfaces. It makes good use of namespaces, modern C++ features, and compile-time concept checking. The suggested improvements are minor and mainly focus on enhancing clarity and robustness.
Great job on implementing this example of modern C++ polymorphism!
polymorphism/CMakeLists.txt (4)
1-3: LGTM: Appropriate use of latest CMake version and project declaration.The use of CMake 3.29 and the project declaration with version and language specification align well with the project's intention to leverage the latest features. This setup provides access to the most recent CMake capabilities and clearly defines the project parameters.
7-15: LGTM: Well-structured executable target configuration.The executable target is well-defined with explicitly listed source files, which is appropriate for this small project. The use of C++23 and the clear separation of public and private include directories demonstrate good CMake practices and align with the project's goals.
17-23: LGTM: Excellent testing configuration with clear status messages.The testing setup is well-structured, providing flexibility through the
POLYMORPHISM_ENABLE_TESTINGoption. The addition of status messages for both enabled and disabled states enhances the build process transparency. This configuration follows CMake best practices for conditional test inclusion.
1-23: Excellent CMake configuration that aligns with project goals.This CMake configuration file is well-structured, comprehensive, and follows modern CMake best practices. It successfully implements the project's intention to use the latest C++ and CMake features while providing flexibility for building and testing. The clear organization and appropriate use of CMake commands make this configuration both effective and maintainable.
polymorphism/test/CMakeLists.txt (4)
1-10: LGTM! CMake and FetchContent setup aligns with project goals.The CMake minimum version and FetchContent setup for Boost UT are well-configured. Using CMake 3.29 and fetching the latest Boost UT version aligns with the project's goal of using the latest features.
12-19: Well-structured library target setup.The
polymorphism_libtarget is set up correctly using modern CMake practices. Good job on:
- Using C++23 standard, aligning with the project goals.
- Properly separating public and private include directories, enhancing encapsulation.
30-30: Correct target linking.The
test_consumeexecutable is properly linked withpolymorphism_libusing the appropriate PRIVATE visibility.
32-36: Well-configured test registration.The test registration for
test_consumeis correctly set up. Good job on:
- Using the correct command structure for
add_test.- Setting the working directory to
${CMAKE_CURRENT_BINARY_DIR}, which is a best practice for test execution.polymorphism/README.md (4)
35-47: Well-structured test instructions.The test instructions provide clear and concise commands for building and running tests. This section is easy to follow and requires no changes.
49-100: Excellent explanation of the classic polymorphism approach.The explanation of the classic approach using abstract classes is thorough and well-illustrated with relevant code examples. This section provides a clear understanding of how polymorphism is implemented using inheritance in C++.
100-170: Comprehensive explanation of the modern polymorphism approach.The explanation of the modern approach using concepts is thorough and well-illustrated with relevant code examples. The section effectively communicates the advantages of this approach, such as non-intrusiveness and flexibility, while also discussing the trade-offs and considerations for implementation. This balanced presentation provides readers with a clear understanding of when and how to use the modern approach.
1-193: Excellent README for C++ polymorphism example!This README file provides a comprehensive and well-structured guide to understanding and implementing polymorphism in C++. It covers both classic and modern approaches, includes clear build and test instructions, and offers detailed explanations with relevant code examples. The minor formatting and grammatical issues identified in the review can be easily addressed, and they don't detract from the overall high quality of the document.
Great job on creating such an informative and user-friendly resource for C++ developers!
🧰 Tools
🪛 LanguageTool
[uncategorized] ~8-~8: Possible missing comma found.
Context: ... implementation inherits. 2. The modern approach using [concepts](https://en.cppreferenc...(AI_HYDRA_LEO_MISSING_COMMA)
[uncategorized] ~21-~21: Possible missing comma found.
Context: ...ymorphism -S polymorphismFor debug builds usebash cmake -D CMAKE_BUILD_TYPE=...(AI_HYDRA_LEO_MISSING_COMMA)
[uncategorized] ~174-~174: Use a comma before ‘and’ if it connects two independent clauses (unless they are closely connected and short).
Context: ...ason. It looks promising and lightweight and it was written by [Krzysztof Jusiak](ht...(COMMA_COMPOUND_SENTENCE)
🪛 Markdownlint
174-174: Expected: 0 or 2; Actual: 3
Trailing spaces(MD009, no-trailing-spaces)
20-20: null
Fenced code blocks should be surrounded by blank lines(MD031, blanks-around-fences)
| // Explicit template instantiation | ||
| template std::string consume<Impl>(Impl&); |
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🧹 Nitpick (assertive)
LGTM! Consider enhancing the comment.
The explicit template instantiation is correct and a good practice. It ensures that the consume<Impl> function is available in this translation unit, which can help with compilation times and reduce code bloat.
Consider enhancing the comment to provide more context:
// Explicit template instantiation for Impl typeThis addition clarifies which specific type is being instantiated.
| #ifndef POYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP | ||
| #define POYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP |
There was a problem hiding this comment.
🧹 Nitpick (assertive)
Fix typo in include guard macro and consider a more unique name.
There's a typo in the include guard macro name: "POYMORPHISM" should be "POLYMORPHISM". Additionally, to ensure uniqueness and prevent potential conflicts with other libraries, consider using a more specific prefix.
Apply this diff to fix the typo and use a more unique macro name:
-#ifndef POYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP
-#define POYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP
+#ifndef CPLUSPLUS_PRIMER_POLYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP
+#define CPLUSPLUS_PRIMER_POLYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP
// ... (rest of the file)
-#endif // POYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP
+#endif // CPLUSPLUS_PRIMER_POLYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPPAlso applies to: 12-12
polymorphism/include/polymorphism/consume_class_that_adheres_to_concept.hpp
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@coderabbitai, please create code change suggestions that add |
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Tip For best results, initiate chat on the files or code changes. @daixtrose, I've prepared the code change suggestions to add Here are the updated include guards: 1. polymorphism/include/polymorphism/consume_class_that_adheres_to_concept.hpp #ifndef CPLUSPLUS_PRIMER_POLYMORPHISM_CONSUME_CLASS_THAT_ADHERES_TO_CONCEPT_HPP
#define CPLUSPLUS_PRIMER_POLYMORPHISM_CONSUME_CLASS_THAT_ADHERES_TO_CONCEPT_HPP
// ... rest of the file ...
#endif // CPLUSPLUS_PRIMER_POLYMORPHISM_CONSUME_CLASS_THAT_ADHERES_TO_CONCEPT_HPP2. polymorphism/include/polymorphism/consume_class_with_interface.hpp #ifndef CPLUSPLUS_PRIMER_POLYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP
#define CPLUSPLUS_PRIMER_POLYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP
// ... rest of the file ...
#endif // CPLUSPLUS_PRIMER_POLYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP3. polymorphism/include/polymorphism/has_super_cool_features.hpp #ifndef CPLUSPLUS_PRIMER_POLYMORPHISM_HAS_SUPER_COOL_FEATURES_HPP
#define CPLUSPLUS_PRIMER_POLYMORPHISM_HAS_SUPER_COOL_FEATURES_HPP
// ... rest of the file ...
#endif // CPLUSPLUS_PRIMER_POLYMORPHISM_HAS_SUPER_COOL_FEATURES_HPP4. polymorphism/include/polymorphism/i_super_cool_features.hpp #ifndef CPLUSPLUS_PRIMER_POLYMORPHISM_I_SUPER_COOL_FEATURES_HPP
#define CPLUSPLUS_PRIMER_POLYMORPHISM_I_SUPER_COOL_FEATURES_HPP
// ... rest of the file ...
#endif // CPLUSPLUS_PRIMER_POLYMORPHISM_I_SUPER_COOL_FEATURES_HPP5. polymorphism/include/polymorphism/impl_with_interface.hpp #ifndef CPLUSPLUS_PRIMER_POLYMORPHISM_IMPL_WITH_INTERFACE_HPP
#define CPLUSPLUS_PRIMER_POLYMORPHISM_IMPL_WITH_INTERFACE_HPP
// ... rest of the file ...
#endif // CPLUSPLUS_PRIMER_POLYMORPHISM_IMPL_WITH_INTERFACE_HPP6. polymorphism/include/polymorphism/impl_without_interface.hpp #ifndef CPLUSPLUS_PRIMER_POLYMORPHISM_IMPL_WITHOUT_INTERFACE_HPP
#define CPLUSPLUS_PRIMER_POLYMORPHISM_IMPL_WITHOUT_INTERFACE_HPP
// ... rest of the file ...
#endif // CPLUSPLUS_PRIMER_POLYMORPHISM_IMPL_WITHOUT_INTERFACE_HPPI've updated the include guards by adding the (_/) (•_•) (💭) ✏️ Learnings added
🔗 Analysis chain@daixtrose, to create the code change suggestions that add @daixtrose, thank you for pointing that out. It seems the previous script did not produce any output due to an issue with the 🏁 Scripts executedThe following scripts were executed for the analysis: Script: #!/bin/bash
# Find all header files under the 'polymorphism' directory
fd -e h -e hpp polymorphism | while read file; do
# Extract the current include guard macro from the file
guard=$(grep -E '^#\s*(ifndef|define)\s+\w+' "$file" | awk '{print $2}' | head -n1)
echo "$file: $guard"
done
Length of output: 41 Script: #!/bin/bash
# Find all header files under the 'polymorphism' directory
fd -e h -e hpp . polymorphism | while read file; do
# Extract the current include guard macro from the file
guard=$(grep -E '^#\s*(ifndef|define)\s+\w+' "$file" | awk '{print $2}' | head -n1)
echo "$file: $guard"
done
Length of output: 2575 |
|
@coderabbitai, thanks for your code change suggestions. Can you please provide them so that I can click on them and they will be immediately applied? |
|
Tip For best results, initiate chat on the files or code changes. @daixtrose, I'm sorry, but I'm unable to provide code change suggestions that can be immediately applied through clicks. Please manually update the include guards as per the suggestions I provided previously. Let me know if there's anything else I can assist you with. (_/) (•_•) (") |
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Actionable comments posted: 11
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📒 Files selected for processing (7)
- polymorphism/CMakeLists.txt (1 hunks)
- polymorphism/README.md (1 hunks)
- polymorphism/include/polymorphism/consume_class_that_adheres_to_concept.hpp (1 hunks)
- polymorphism/include/polymorphism/consume_class_with_interface.hpp (1 hunks)
- polymorphism/include/polymorphism/i_super_cool_features.hpp (1 hunks)
- polymorphism/include/polymorphism/impl_with_interface.hpp (1 hunks)
- polymorphism/include/polymorphism/impl_without_interface.hpp (1 hunks)
🧰 Additional context used
📓 Learnings (1)
polymorphism/CMakeLists.txt (1)
Learnt from: daixtrose PR: daixtrose/cplusplus-primer#10 File: polymorphism/CMakeLists.txt:1-3 Timestamp: 2024-10-16T21:16:21.134Z Learning: For the project `polymorphism`, the user intentionally uses the latest and greatest C++ and CMake features.
🪛 Markdownlint
polymorphism/README.md
174-174: Expected: 0 or 2; Actual: 3
Trailing spaces(MD009, no-trailing-spaces)
20-20: null
Fenced code blocks should be surrounded by blank lines(MD031, blanks-around-fences)
🔇 Additional comments (18)
polymorphism/include/polymorphism/consume_class_with_interface.hpp (1)
4-4: Include statement looks good.The include statement for
i_super_cool_features.hppis appropriate and suggests a well-organized project structure.polymorphism/include/polymorphism/consume_class_that_adheres_to_concept.hpp (3)
4-4: Includes look goodThe necessary headers are properly included. Good job on adding the
<string>header as suggested in the previous review.Also applies to: 6-6
8-8: Namespace usage is correctThe
modernnamespace is properly used to encapsulate the function declaration, which is a good practice for organizing code and avoiding naming conflicts.Also applies to: 13-13
1-2:⚠️ Potential issueFix typo in include guard macro name
The include guard macro name contains a typo. "POYMORPHISM" should be "POLYMORPHISM".
Please apply the following changes:
-#ifndef POYMORPHISM_CONSUME_CLASS_THAT_ADHERES_TO_CONCEPT_HPP -#define POYMORPHISM_CONSUME_CLASS_THAT_ADHERES_TO_CONCEPT_HPP +#ifndef POLYMORPHISM_CONSUME_CLASS_THAT_ADHERES_TO_CONCEPT_HPP +#define POLYMORPHISM_CONSUME_CLASS_THAT_ADHERES_TO_CONCEPT_HPP // ... (rest of the file) -#endif // POYMORPHISM_CONSUME_CLASS_THAT_ADHERES_TO_CONCEPT_HPP +#endif // POLYMORPHISM_CONSUME_CLASS_THAT_ADHERES_TO_CONCEPT_HPPAlso applies to: 15-15
polymorphism/include/polymorphism/impl_with_interface.hpp (1)
9-9: LGTM: Namespace declaration and closing.The namespace declaration and closing for
classicare correctly implemented.Also applies to: 24-24
polymorphism/include/polymorphism/impl_without_interface.hpp (1)
1-28: Overall, well-implemented modern C++ classThe
Implclass demonstrates good use of modern C++ features and follows best practices. The implementation is clean and efficient. Consider addressing the minor suggestions to further improve the code quality.polymorphism/include/polymorphism/i_super_cool_features.hpp (3)
1-5: LGTM: Proper use of include guards and necessary includes.The include guards are correctly implemented and follow a consistent naming convention. The inclusion of the header is appropriate for the use of std::string in the interface.
6-14: LGTM: Well-structured namespace and improved documentation.The use of the 'classic' namespace is appropriate for encapsulating the interface. The class documentation has been significantly improved, addressing the suggestions from the previous review. It now provides a clear description of the interface's purpose and details about its methods, enhancing the code's self-documentation.
1-24: LGTM: Well-structured and consistent file.The overall structure of the file is clean and follows common C++ conventions. The naming is consistent, and the file is properly organized with include guards, necessary includes, namespace declaration, and interface definition. The file ends correctly with the closing of the namespace and the include guard.
polymorphism/CMakeLists.txt (5)
1-3: LGTM: Appropriate use of latest CMake version and project declaration.The use of CMake 3.29 and the project declaration with version and language specification align well with the project's intention to use the latest features. This setup provides access to the most recent CMake capabilities and clearly defines the project parameters.
5-6: LGTM: Well-documented testing option with appropriate default.The
POLYMORPHISM_ENABLE_TESTINGoption is well-defined and documented. Using${PROJECT_IS_TOP_LEVEL}as the default value is a good practice for subproject compatibility, and the comment clearly explains its purpose.
8-12: LGTM: Clear and concise executable target declaration.The executable target is well-defined with explicitly listed source files. This approach is appropriate for a small project and aligns with your preference for clarity in CMake configurations.
14-16: LGTM: Appropriate target configuration with modern C++ standard.The target is well-configured with C++23 as the compile feature, which aligns with the project's goal of using the latest C++ features. The separation of public and private include directories is a good practice for maintaining a clean interface.
18-24: LGTM: Well-structured conditional testing setup with informative messages.The testing configuration is well-implemented, providing flexibility through the
POLYMORPHISM_ENABLE_TESTINGoption. The addition of status messages enhances build configuration clarity, which is helpful for debugging. The structure follows CMake best practices for organizing tests.polymorphism/README.md (4)
1-10: Great introduction and summary!The summary provides a clear and concise overview of the two approaches to polymorphism in C++ and mentions the use of the ut testing framework. This sets the stage well for the rest of the document.
35-47: Well-documented test instructions.The test instructions are clear and concise, providing all necessary information for users to build and run tests. This section will be very helpful for developers working on the project.
49-170: Excellent explanations of classic and modern polymorphism approaches.The code explanations section provides detailed and clear information about both the classic and modern approaches to polymorphism in C++. The code examples effectively illustrate the concepts and are well-formatted. The explanations cover important aspects such as:
- Abstract classes and inheritance for the classic approach.
- Concepts and constraints for the modern approach.
- Advantages and trade-offs of each method.
- Practical usage examples for both approaches.
This section will be extremely valuable for developers learning about C++ polymorphism or comparing the two approaches.
1-193: Excellent README file for the C++ polymorphism example.This README file is well-structured, comprehensive, and informative. It covers all necessary aspects of the C++ polymorphism example, including:
- A clear summary of the two polymorphism approaches.
- Detailed build and test instructions.
- In-depth explanations of both classic and modern polymorphism techniques.
- Information about the testing framework used.
The explanations are clear and accompanied by relevant code snippets, making it easy for readers to understand and implement the concepts. The minor formatting issues mentioned in previous comments are easily addressable and don't detract from the overall quality of the document.
This README will serve as an excellent resource for developers working with C++ polymorphism, whether they're learning the concepts or implementing them in their projects.
🧰 Tools
🪛 Markdownlint
174-174: Expected: 0 or 2; Actual: 3
Trailing spaces(MD009, no-trailing-spaces)
20-20: null
Fenced code blocks should be surrounded by blank lines(MD031, blanks-around-fences)
| #ifndef POLYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP | ||
| #define POLYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP |
There was a problem hiding this comment.
🧹 Nitpick (assertive)
Consider using a more unique prefix for the include guard macro.
While the typo has been fixed, consider using a more specific prefix to ensure uniqueness and prevent potential conflicts with other libraries. For example:
-#ifndef POLYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP
-#define POLYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP
+#ifndef CPLUSPLUS_PRIMER_POLYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP
+#define CPLUSPLUS_PRIMER_POLYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP
// ... (rest of the file)
-#endif // POLYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPP
+#endif // CPLUSPLUS_PRIMER_POLYMORPHISM_CONSUME_CLASS_WITH_INTERFACE_HPPThis change would make the include guard more specific to your project.
Also applies to: 12-12
| namespace classic { | ||
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| std::string consume(ISuperCoolFeatures& f); | ||
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| } // namespace classic |
There was a problem hiding this comment.
🧹 Nitpick (assertive)
Namespace and function declaration look good. Consider adding a brief comment.
The use of the "classic" namespace and the function declaration for consume are well-structured. To improve clarity, consider adding a brief comment explaining the purpose of the consume function. For example:
namespace classic {
// Consumes an object implementing the ISuperCoolFeatures interface
// and returns a string representation of the result.
std::string consume(ISuperCoolFeatures& f);
} // namespace classicThis addition would provide context for developers who might use this function in the future.
| // declaration with concept constraint | ||
| std::string consume(has_super_cool_features auto& s); |
There was a problem hiding this comment.
🧹 Nitpick (assertive)
Enhance function documentation
While the function declaration looks good and uses modern C++ features as intended, the documentation could be improved for better clarity.
Consider using a Doxygen-style comment for better documentation. Here's a suggested improvement:
/**
* @brief Consumes an object that adheres to the has_super_cool_features concept.
* @param s Reference to an object satisfying the has_super_cool_features concept.
* @return A string result after consuming the object.
*/
std::string consume(has_super_cool_features auto& s);| #ifndef POYMORPHISM_IMPL_WITH_INTERFACE_HPP | ||
| #define POYMORPHISM_IMPL_WITH_INTERFACE_HPP |
There was a problem hiding this comment.
Fix typo in include guard macro name.
There's a typo in the include guard macro name. "POYMORPHISM" should be "POLYMORPHISM".
Please apply the following changes:
-#ifndef POYMORPHISM_IMPL_WITH_INTERFACE_HPP
-#define POYMORPHISM_IMPL_WITH_INTERFACE_HPP
+#ifndef POLYMORPHISM_IMPL_WITH_INTERFACE_HPP
+#define POLYMORPHISM_IMPL_WITH_INTERFACE_HPP
// ... (rest of the file)
-#endif // POYMORPHISM_IMPL_WITH_INTERFACE_HPP
+#endif // POLYMORPHISM_IMPL_WITH_INTERFACE_HPPAlso applies to: 26-26
| std::string coolFeature() const noexcept override { return s_; } | ||
| void set(std::string s) noexcept override | ||
| { | ||
| s_ = std::move(s); | ||
| } |
There was a problem hiding this comment.
🧹 Nitpick (assertive)
LGTM: Public methods implementation.
The coolFeature() and set(std::string s) methods correctly override the interface methods and are marked as noexcept. The use of std::move in the set method is efficient for string assignment.
Consider changing the set method's parameter to const std::string& for more flexibility:
void set(const std::string& s) noexcept override
{
s_ = s; // The move will be implicitly applied here
}This allows for more flexible use of the method with both lvalues and rvalues.
| #ifndef POYMORPHISM_IMPL_WITHOUT_INTERFACE_HPP | ||
| #define POYMORPHISM_IMPL_WITHOUT_INTERFACE_HPP |
There was a problem hiding this comment.
Fix typo in include guard macro name
There's a typo in the include guard macro name. "POLYMORPHISM" is misspelled as "POYMORPHISM".
Please apply the following change:
-#ifndef POYMORPHISM_IMPL_WITHOUT_INTERFACE_HPP
-#define POYMORPHISM_IMPL_WITHOUT_INTERFACE_HPP
+#ifndef POLYMORPHISM_IMPL_WITHOUT_INTERFACE_HPP
+#define POLYMORPHISM_IMPL_WITHOUT_INTERFACE_HPP
// ... (rest of the file)
-#endif // POYMORPHISM_IMPL_WITHOUT_INTERFACE_HPP
+#endif // POLYMORPHISM_IMPL_WITHOUT_INTERFACE_HPPAlso applies to: 28-28
| std::string s_ { "<default value>" }; // with default member initializer (C++11) | ||
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| public: | ||
| std::string coolFeature() const noexcept { return s_; } |
There was a problem hiding this comment.
🧹 Nitpick (assertive)
Consider adding [[nodiscard]] attribute to coolFeature()
The coolFeature() method returns a value that is likely intended to be used. Consider adding the [[nodiscard]] attribute to encourage using its return value and prevent accidental value dropping.
Suggested change:
- std::string coolFeature() const noexcept { return s_; }
+ [[nodiscard]] std::string coolFeature() const noexcept { return s_; }📝 Committable suggestion
‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.
| std::string coolFeature() const noexcept { return s_; } | |
| [[nodiscard]] std::string coolFeature() const noexcept { return s_; } |
| class ISuperCoolFeatures { | ||
| public: | ||
| [[nodiscard]] virtual std::string coolFeature() const = 0; // Pure virtual function | ||
| virtual void set(std::string s) = 0; // Pure virtual function | ||
| virtual ~ISuperCoolFeatures() = default; // Virtual destructor | ||
| }; |
There was a problem hiding this comment.
🧹 Nitpick (assertive)
LGTM: Well-designed interface with proper use of C++ features.
The ISuperCoolFeatures interface is well-structured, following C++ best practices for abstract classes. The use of pure virtual functions and a virtual destructor is correct. The [[nodiscard]] attribute on coolFeature() is a good practice to prevent accidental ignoring of the return value.
Consider adding the override specifier to the destructor for consistency and to make the interface more robust:
virtual ~ISuperCoolFeatures() override = default;This change would ensure that if the interface is inherited from another base class in the future, the destructor will be correctly overridden.
polymorphism/README.md
Outdated
| ## Testing | ||
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| In this example, I use [µt](https://github.com/boost-ext/ut) as testing framework for no good reason. It looks promising and lightweight, and it was written by [Krzysztof Jusiak](https://github.com/krzysztof-jusiak) whom I adore for his outstanding C++ programming skills and his [C++ Tip of The Week](https://github.com/tip-of-the-week/cpp) collection of crazy C++ riddles. | ||
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| The one-header version of it is pulled into the project via the CMake call | ||
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| ```cmake | ||
| FetchContent_Declare(ut | ||
| URL https://raw.githubusercontent.com/boost-ext/ut/refs/heads/master/include/boost/ut.hpp | ||
| DOWNLOAD_NO_EXTRACT TRUE | ||
| SOURCE_DIR ut | ||
| ) | ||
| FetchContent_MakeAvailable(ut) | ||
| ``` | ||
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| and the directory to which the header is downloaded is added to the search path set for the build of the test executables: | ||
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| ```cmake | ||
| target_include_directories(test_consume PUBLIC "${ut_SOURCE_DIR}") | ||
| ``` | ||
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| Please refer to [this slidedeck](https://boost-ext.github.io/ut/denver-cpp-2019/#/) for further documentation of this test library. |
There was a problem hiding this comment.
🧹 Nitpick (assertive)
Informative testing section with helpful CMake snippets.
The testing section provides clear information about using the µt testing framework, including CMake code snippets for including the framework. The link to further documentation is a valuable addition.
Consider making the following minor improvements:
- Remove the trailing spaces at the end of line 174.
- Add a brief explanation of why µt was chosen over other testing frameworks. This context could be helpful for users who are new to C++ testing or are considering different options.
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🪛 Markdownlint
174-174: Expected: 0 or 2; Actual: 3
Trailing spaces(MD009, no-trailing-spaces)
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Actionable comments posted: 9
📜 Review details
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Review profile: ASSERTIVE
📒 Files selected for processing (3)
- polymorphism/README.md (1 hunks)
- polymorphism/include/polymorphism/impl_with_interface.hpp (1 hunks)
- polymorphism/include/polymorphism/impl_without_interface.hpp (1 hunks)
🧰 Additional context used
🪛 Markdownlint
polymorphism/README.md
20-20: null
Fenced code blocks should be surrounded by blank lines(MD031, blanks-around-fences)
🔇 Additional comments (7)
polymorphism/include/polymorphism/impl_with_interface.hpp (3)
1-8: LGTM: Include guards and includes are correctly implemented.The include guards are properly formatted, and the necessary headers are included. The previously reported typo in the include guard macro name has been fixed.
9-10: LGTM: Appropriate namespace usage.The
classicnamespace is correctly used, which is consistent with the implementation of classic polymorphism and helps prevent naming conflicts.
24-26: LGTM: Proper closure of namespace and include guard.The namespace is correctly closed with an appropriate comment, and the include guard is properly terminated.
polymorphism/include/polymorphism/impl_without_interface.hpp (3)
1-7: LGTM: Include guards and includes are correctly implemented.The include guards use the correct naming convention, matching the file name. Necessary headers are included for the implementation.
11-12: LGTM: Good use of default member initializer.The private member
s_is correctly declared with a default initializer, which is a good use of C++11 features. The naming convention for private members is consistent.
22-24: LGTM: Excellent use of static assertion.The static assertion is a great practice to ensure the
Implclass adheres to thehas_super_cool_featuresconcept. The error message is descriptive and helpful, which will aid developers if the assertion fails.polymorphism/README.md (1)
1-193: Excellent README with comprehensive coverage of C++ polymorphism approaches!This README provides a thorough and well-structured guide to understanding and implementing both classic and modern approaches to polymorphism in C++. The inclusion of build instructions, test instructions, and detailed code explanations makes this an invaluable resource for developers working on this project or learning about C++ polymorphism.
The suggested improvements throughout the review are minor and aimed at enhancing clarity, providing additional context, and improving formatting. Implementing these suggestions will further elevate the quality of this already impressive documentation.
Great job on creating such a comprehensive and informative README!
🧰 Tools
🪛 Markdownlint
20-20: null
Fenced code blocks should be surrounded by blank lines(MD031, blanks-around-fences)
| class Impl | ||
| : public ISuperCoolFeatures { | ||
| private: | ||
| std::string s_ { "<default value>" }; // with default member initializer (C++11) |
There was a problem hiding this comment.
🧹 Nitpick (assertive)
LGTM: Class declaration and member initialization are well-implemented.
The Impl class correctly inherits from ISuperCoolFeatures, and the private member s_ uses a C++11 default member initializer.
Consider adding a brief comment explaining the purpose of the s_ member variable for improved code documentation. For example:
private:
std::string s_ { "<default value>" }; // Stores the current feature value| public: | ||
| std::string coolFeature() const noexcept override { return s_; } | ||
| void set(std::string s) noexcept override | ||
| { | ||
| s_ = std::move(s); | ||
| } | ||
| }; |
There was a problem hiding this comment.
🛠️ Refactor suggestion
LGTM: Public methods are correctly implemented.
The coolFeature() and set(std::string s) methods properly override the interface methods and are marked as noexcept. The use of std::move in the set method is efficient for string assignment.
Consider changing the set method's parameter to const std::string& for more flexibility:
void set(const std::string& s) noexcept override
{
s_ = s; // The move will be implicitly applied here for rvalues
}This allows for more flexible use of the method with both lvalues and rvalues, potentially improving performance in some cases.
| namespace modern { | ||
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| class Impl { |
There was a problem hiding this comment.
🧹 Nitpick (assertive)
Consider using a more descriptive class name.
While Impl is concise, it might be too generic in a larger codebase. Consider a more descriptive name that reflects the class's purpose or functionality, such as ModernFeatureImpl or ConceptBasedImpl.
| public: | ||
| [[nodiscard]] std::string coolFeature() const noexcept { return s_; } | ||
| void set(std::string s) noexcept | ||
| { | ||
| s_ = std::move(s); | ||
| } | ||
| }; |
There was a problem hiding this comment.
🧹 Nitpick (assertive)
LGTM: Well-implemented public methods with a minor suggestion.
The public methods are well-implemented:
- Good use of
[[nodiscard]]oncoolFeature(). - Both methods are correctly marked as
noexcept. - Efficient use of
std::moveinset().
Minor suggestion: Consider using std::string_view for the parameter of set() if you're using C++17 or later, as it can be more efficient for string operations that don't need ownership.
- void set(std::string s) noexcept
+ void set(std::string_view s) noexcept
{
- s_ = std::move(s);
+ s_ = s;
}📝 Committable suggestion
‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.
| public: | |
| [[nodiscard]] std::string coolFeature() const noexcept { return s_; } | |
| void set(std::string s) noexcept | |
| { | |
| s_ = std::move(s); | |
| } | |
| }; | |
| public: | |
| [[nodiscard]] std::string coolFeature() const noexcept { return s_; } | |
| void set(std::string_view s) noexcept | |
| { | |
| s_ = s; | |
| } | |
| }; |
| # C++ Polymorphism Example | ||
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| ## Summary | ||
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| This example shows two different ways to implement [polymorphism](https://en.wikipedia.org/wiki/Polymorphism_(computer_science)) in C++: | ||
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| 1. The classic approach using an [abstract class](https://en.cppreference.com/w/cpp/language/abstract_class) which is used to define an interface and from which the implementation inherits. | ||
| 2. The modern approach using [concepts](https://en.cppreference.com/w/cpp/language/constraints) to declare features a type must have. | ||
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| In addition, this directory contains an example about how to perform unit tests using the [ut testing framework](https://github.com/boost-ext/ut). | ||
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There was a problem hiding this comment.
🧹 Nitpick (assertive)
Great introduction and summary!
The introduction provides a clear and concise overview of the two approaches to polymorphism in C++ and mentions the use of the ut testing framework. This sets the stage well for the rest of the document.
Consider adding a brief explanation of why understanding these two approaches is important for C++ developers. This could help motivate readers to explore the examples further.
| ## Build Instructions | ||
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| ### Preparation | ||
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| Create a subdirectory `build_polymorphism` and prepare the build system for the source located in `polymorphism` in this subdirectory: For release builds use | ||
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| ```bash | ||
| cmake -D CMAKE_BUILD_TYPE=Release -B build_polymorphism -S polymorphism | ||
| ``` | ||
| For debug builds use | ||
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| ```bash | ||
| cmake -D CMAKE_BUILD_TYPE=Debug -B build_polymorphism -S polymorphism | ||
| ``` | ||
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| ### Building the `polymorphism` project | ||
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| Call `cmake` from the top level like this: | ||
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| ```bash | ||
| cmake --build build_polymorphism --config Release --target polymorphism --parallel | ||
| ``` |
There was a problem hiding this comment.
🧹 Nitpick (assertive)
Clear and comprehensive build instructions.
The build instructions are well-structured and provide clear commands for both release and debug builds. This will be very helpful for users trying to build the project.
Consider making the following improvements:
- Add a brief explanation of why CMake is being used and its benefits for this project.
- Include information about any prerequisites or dependencies needed to build the project.
- Add a blank line before and after the code block at line 20 for consistency with Markdown best practices:
cmake -D CMAKE_BUILD_TYPE=Release -B build_polymorphism -S polymorphism
+For debug builds use
+
🧰 Tools
🪛 Markdownlint
20-20: null
Fenced code blocks should be surrounded by blank lines(MD031, blanks-around-fences)
| ## Test Instructions | ||
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| ### Build the tests | ||
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| ```bash | ||
| VERBOSE=1 cmake --build build_polymorphism --clean-first --config Debug --target all --parallel | ||
| ``` | ||
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| ### Run the tests | ||
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| ```bash | ||
| ctest --test-dir build_polymorphism --output-on-failure --build-config Debug | ||
| ``` |
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🧹 Nitpick (assertive)
Concise test instructions.
The test instructions are clear and provide the necessary commands to build and run the tests.
Consider adding the following to enhance this section:
- A brief explanation of what the tests cover and why they are important.
- Information on how to interpret the test results.
- Guidance on what to do if tests fail.
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| // ... private members and member functions omitted ... | ||
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| public: | ||
| std::string coolFeature() const override { return s_; } | ||
| void set(std::string s) override | ||
| { | ||
| // ... implementation omitted ... | ||
| } | ||
| }; | ||
| ``` | ||
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| A variable (aka instantiation) of type `Impl` can be passed as argument to any function that expects an argument of its interface type `ISuperCoolFeatures`. | ||
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| In our example, we define a function which has one argument of type `ISuperCoolFeatures`, and returns a `std::string`: | ||
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| ```c++ | ||
| std::string consume(ISuperCoolFeatures& f); | ||
| ``` | ||
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| We then pass an argument of type `Impl` to it, e.g. like this: | ||
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| ```c++ | ||
| Impl i; | ||
| consume(i); | ||
| ``` | ||
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| Since it is best practice, the example code puts the type and function definitions into namespaces. | ||
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| ### Modern Approach | ||
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| In modern C++, interfaces can also be defined via [concepts](https://en.cppreference.com/w/cpp/language/constraints), which can be used to declare what features a concrete class must have. It is slightly more powerful in what can be described. | ||
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| It also has a great advantage that it is non-intrusive, i.e. it does not require a concrete class to inherit from a certain interface class. This is of advantage when you are not owner of the code of a class that you want to use and cannot change its declaration and definition. | ||
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| This means that objects of completely unrelated classes can be passed as arguments to a member function (aka method) or a free function, if they all have certain member functions defined. | ||
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| From a code structuring point of view, this means that the cohesion between different parts of the code is reduced. | ||
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| In this example, we have defined such an interface specification as a concept: | ||
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| ```c++ | ||
| template <typename T> | ||
| concept has_super_cool_features = requires(T t, std::string s) { | ||
| { t.coolFeature() } -> std::convertible_to<std::string>; | ||
| { t.set(s) } -> std::same_as<void>; | ||
| }; | ||
| ``` | ||
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| We then declare a function that takes arguments whose type adheres to the constraints defined by the concept: | ||
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| ```c++ | ||
| std::string consume(has_super_cool_features auto& s); | ||
| ``` | ||
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| and can use it in the very same way like in the classic case: | ||
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| ```c++ | ||
| Impl i; | ||
| consume(i); | ||
| ``` | ||
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| In this approach, our implementation is defined **without** inheritance: | ||
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| ```c++ | ||
| class Impl { | ||
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| // ... | ||
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| public: | ||
| std::string coolFeature() const { /* ... some code ... */ } | ||
| void set(std::string s) | ||
| { | ||
| // code omitted | ||
| } | ||
| }; | ||
| ``` | ||
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| To catch errors in the implementation before the class gets uses somewhere else in the code, it suffices to check against the concept like this: | ||
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| ```c++ | ||
| static_assert(has_super_cool_features<Impl>); | ||
| ``` | ||
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| Please note, that this modern approach with its advantages in code decoupling, flexibility and a more powerful description of its features comes at a price: | ||
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| Functions that use `<some concept> auto` as parameter type are *generic* and this requires either their implicit or their explicit instantiation. | ||
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| Implicit instantiation of the function can take place if its **definition** is visible at the point of usage. | ||
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| In this example, we use explicit instantiation to show the possibility to clearly separate the definition (implementation) of the generic function from its declaration. | ||
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| You can find the definition of `consume` in `src/consume_class_that_adheres_to_concept.ipp` which is then included into `src/consume_class_that_adheres_to_concept.cpp`. In the latter file we also place all explicit instantiations of `consume`: | ||
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| ```c++ | ||
| // explicit template instantiation | ||
| template std::string consume<Impl>(Impl&); | ||
| ``` | ||
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| As an alternative, the *definition* of `consume` could be in the header `include/polymorphism/consume_class_that_adheres_to_concept.hpp`. Then the explicit template instantiation is no longer required. |
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🧹 Nitpick (assertive)
Comprehensive code explanations for both approaches.
The explanations for both the classic and modern approaches to polymorphism are detailed and well-structured. The code snippets effectively illustrate the concepts.
Consider making the following improvements:
- Add comments to the code snippets to highlight key points or explain complex parts.
- Provide a brief comparison of the pros and cons of each approach at the end of this section.
- Include a small, complete example that demonstrates both approaches side-by-side for easy comparison.
| ## Testing | ||
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| In this example, I use [µt](https://github.com/boost-ext/ut) as testing framework for no good reason. It looks promising and lightweight, and it was written by [Krzysztof Jusiak](https://github.com/krzysztof-jusiak) whom I adore for his outstanding C++ programming skills and his [C++ Tip of The Week](https://github.com/tip-of-the-week/cpp) collection of crazy C++ riddles. | ||
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| The one-header version of it is pulled into the project via the CMake call | ||
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| ```cmake | ||
| FetchContent_Declare(ut | ||
| URL https://raw.githubusercontent.com/boost-ext/ut/refs/heads/master/include/boost/ut.hpp | ||
| DOWNLOAD_NO_EXTRACT TRUE | ||
| SOURCE_DIR ut | ||
| ) | ||
| FetchContent_MakeAvailable(ut) | ||
| ``` | ||
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| and the directory to which the header is downloaded is added to the search path set for the build of the test executables: | ||
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| ```cmake | ||
| target_include_directories(test_consume PUBLIC "${ut_SOURCE_DIR}") | ||
| ``` | ||
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| Please refer to [this slidedeck](https://boost-ext.github.io/ut/denver-cpp-2019/#/) for further documentation of this test library. |
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🧹 Nitpick (assertive)
Informative testing section with helpful CMake snippets.
The testing section provides clear information about using the µt testing framework, including CMake code snippets for including the framework. The link to further documentation is a valuable addition.
Consider making the following improvements:
- Explain why µt was chosen over other testing frameworks. This context could be helpful for users who are new to C++ testing or are considering different options.
- Provide a brief example of how to write a simple test using µt, to give readers a quick start.
- Add information on how to add new tests to the project.
Summary by CodeRabbit
New Features
Bug Fixes
Documentation
Tests