Lisp Interpreter — Final Project for MIT 6.101: Fundamentals of Programming

This is a complete Python-based interpreter for a Scheme-like Lisp dialect, built as the final project for MIT 6.101 (Fundamentals of Programming). The interpreter parses and evaluates Scheme expressions, handles user-defined functions, and supports special forms like let, set!, and del.

🧠 Features

• Full support for:
  • Arithmetic and boolean operations
  • Proper lists using cons, car, cdr, list, and append
  • Logical constructs: if, and, or, begin
  • Lexical scoping and user-defined functions via define and lambda
  • Variable mutation and deletion with set! and del
  • Scoped variable declarations using let
• Custom error classes for robust debugging
• REPL interface and .scm file loader

✅ Completed Milestones

• ✅ Parsing and tokenization
• ✅ Recursive evaluation
• ✅ Support for built-in and user-defined functions
• ✅ Custom special forms
• ✅ Passes all MIT 6.101 test cases, including edge cases and deep nesting

python3 lab.py test_inputs/your_file.scm