better-document CRC32

Sources/CRC/CRC32.swift

@@ -1,39 +1,48 @@
 import Base16
 
+/// The value of a [CRC32](https://en.wikipedia.org/wiki/Cyclic_redundancy_check) checksum.
 @frozen public
 struct CRC32:Hashable, Sendable
 {
+    @_documentation(visibility: internal)
     public static
     let table:[UInt32] = (0 ..< 256).map
     {
         (i:UInt32) in
         (0 ..< 8).reduce(i){ (c, _) in (c & 1 * 0xed_b8_83_20) ^ c >> 1 }
     }
 
+    /// The checksum value as a 32-bit unsigned integer.
     public
     var checksum:UInt32
 
+    /// Creates a new checksum with the specified value.
     @inlinable public
     init(checksum:UInt32 = 0)
     {
         self.checksum = checksum
     }
+
+    /// Computes the checksum of the provided message.
     @inlinable public
-    init(hashing message:some Sequence<UInt8>)
+    init(hashing message:borrowing some Sequence<UInt8>)
     {
         self.init()
         self.update(with: message)
     }
 
+    /// Returns a new checksum by hashing the provided message into the current checksum.
     @inlinable public
-    func updated(with message:some Sequence<UInt8>) -> Self
+    func updated(with message:borrowing some Sequence<UInt8>) -> Self
     {
         var checksum:Self = self
         checksum.update(with: message)
         return checksum
     }
+
+    /// Updates the checksum by hashing the provided message into the existing checksum.
     @inlinable public mutating
-    func update(with message:some Sequence<UInt8>)
+    func update(with message:borrowing some Sequence<UInt8>)
     {
         self.checksum = ~message.reduce(~self.checksum)
         {
@@ -52,6 +61,7 @@ extension CRC32:ExpressibleByIntegerLiteral
 }
 extension CRC32:CustomStringConvertible
 {
+    /// The lowercased hexadecimal representation of the checksum value.
     @inlinable public
     var description:String
     {