lexer cont ('@':cs) = cont TKat cs
lexer cont ('?':cs) = cont TKquestion cs
lexer cont (';':cs) = cont TKsemicolon cs
+lexer cont (':':cs) = cont TKcolon cs
lexer cont (c:cs) = failP "invalid character" [c]
lexChar cont ('\\':'x':h1:h0:'\'':cs)
("in",rest) -> cont TKin rest
("case",rest) -> cont TKcase rest
("of",rest) -> cont TKof rest
- ("coerce",rest) -> cont TKcoerce rest
+ ("cast",rest) -> cont TKcast rest
("note",rest) -> cont TKnote rest
("external",rest) -> cont TKexternal rest
("_",rest) -> cont TKwild rest