Implement DigestOps trait for Digest across CRC types.

src/crc128.rs

@@ -51,11 +51,22 @@ where
         Digest { crc, value }
     }
 
-    pub fn update(&mut self, bytes: &[u8]) {
+    pub const fn finalize(self) -> u128 {
+        finalize(self.crc.algorithm, self.value)
+    }
+}
+
+impl<'a, const L: usize> DigestOps for Digest<'a, u128, Table<L>>
+where
+    Table<L>: private::Sealed,
+{
+    type Width = u128;
+
+    fn update(&mut self, bytes: &[u8]) {
         self.value = self.crc.update(self.value, bytes);
     }
 
-    pub const fn finalize(self) -> u128 {
+    fn finalize(self) -> Self::Width {
         finalize(self.crc.algorithm, self.value)
     }
 }

src/crc16.rs

@@ -51,11 +51,22 @@ where
         Digest { crc, value }
     }
 
-    pub fn update(&mut self, bytes: &[u8]) {
+    pub const fn finalize(self) -> u16 {
+        finalize(self.crc.algorithm, self.value)
+    }
+}
+
+impl<'a, const L: usize> DigestOps for Digest<'a, u16, Table<L>>
+where
+    Table<L>: private::Sealed,
+{
+    type Width = u16;
+
+    fn update(&mut self, bytes: &[u8]) {
         self.value = self.crc.update(self.value, bytes);
     }
 
-    pub const fn finalize(self) -> u16 {
+    fn finalize(self) -> Self::Width {
         finalize(self.crc.algorithm, self.value)
     }
 }

src/crc32.rs

@@ -51,11 +51,22 @@ where
         Digest { crc, value }
     }
 
-    pub fn update(&mut self, bytes: &[u8]) {
+    pub const fn finalize(self) -> u32 {
+        finalize(self.crc.algorithm, self.value)
+    }
+}
+
+impl<'a, const L: usize> DigestOps for Digest<'a, u32, Table<L>>
+where
+    Table<L>: private::Sealed,
+{
+    type Width = u32;
+
+    fn update(&mut self, bytes: &[u8]) {
         self.value = self.crc.update(self.value, bytes);
     }
 
-    pub const fn finalize(self) -> u32 {
+    fn finalize(self) -> Self::Width {
         finalize(self.crc.algorithm, self.value)
     }
 }

src/crc64.rs

@@ -51,11 +51,22 @@ where
         Digest { crc, value }
     }
 
-    pub fn update(&mut self, bytes: &[u8]) {
+    pub const fn finalize(self) -> u64 {
+        finalize(self.crc.algorithm, self.value)
+    }
+}
+
+impl<'a, const L: usize> DigestOps for Digest<'a, u64, Table<L>>
+where
+    Table<L>: private::Sealed,
+{
+    type Width = u64;
+
+    fn update(&mut self, bytes: &[u8]) {
         self.value = self.crc.update(self.value, bytes);
     }
 
-    pub const fn finalize(self) -> u64 {
+    fn finalize(self) -> Self::Width {
         finalize(self.crc.algorithm, self.value)
     }
 }

src/crc8.rs

@@ -51,11 +51,22 @@ where
         Digest { crc, value }
     }
 
-    pub fn update(&mut self, bytes: &[u8]) {
+    pub const fn finalize(self) -> u8 {
+        finalize(self.crc.algorithm, self.value)
+    }
+}
+
+impl<'a, const L: usize> DigestOps for Digest<'a, u8, Table<L>>
+where
+    Table<L>: private::Sealed,
+{
+    type Width = u8;
+
+    fn update(&mut self, bytes: &[u8]) {
         self.value = self.crc.update(self.value, bytes);
     }
 
-    pub const fn finalize(self) -> u8 {
+    fn finalize(self) -> Self::Width {
         finalize(self.crc.algorithm, self.value)
     }
 }

src/lib.rs

@@ -10,6 +10,8 @@
 //!
 //! Using a custom algorithm:
 //! ```rust
+//! use crc::DigestOps;
+//!
 //! const CUSTOM_ALG: crc::Algorithm<u16> = crc::Algorithm {
 //!     width: 16,
 //!     poly: 0x8005,
@@ -79,6 +81,13 @@ pub struct Digest<'a, W: Width, I: Implementation = DefaultImpl> {
     value: W,
 }
 
+pub trait DigestOps {
+    type Width: Width;
+
+    fn update(&mut self, bytes: &[u8]);
+    fn finalize(self) -> Self::Width;
+}
+
 #[cfg(test)]
 mod test {
     use super::{Crc, CRC_32_ISCSI};