nicer error messages for used keywords as identifiers

compiler/lexer.nim

@@ -165,6 +165,10 @@ proc tokToStr*(tok: TToken): string =
       InternalError("tokToStr")
       result = ""
   
+proc prettyTok*(tok: TToken): string =
+  if IsKeyword(tok.tokType): result = "keyword " & tok.ident.s
+  else: result = tokToStr(tok)
+  
 proc PrintTok*(tok: TToken) = 
   write(stdout, TokTypeToStr[tok.tokType])
   write(stdout, " ")

compiler/parser.nim

@@ -69,7 +69,7 @@ proc parMessage(p: TParser, msg: TMsgKind, arg: string = "") =
   lexMessage(p.lex, msg, arg)
 
 proc parMessage(p: TParser, msg: TMsgKind, tok: TToken) = 
-  lexMessage(p.lex, msg, tokToStr(tok))
+  lexMessage(p.lex, msg, prettyTok(tok))
 
 proc skipComment(p: var TParser, node: PNode) = 
   if p.tok.tokType == tkComment: 
@@ -92,11 +92,11 @@ proc optInd(p: var TParser, n: PNode) =
 
 proc expectIdentOrKeyw(p: TParser) = 
   if p.tok.tokType != tkSymbol and not isKeyword(p.tok.tokType): 
-    lexMessage(p.lex, errIdentifierExpected, tokToStr(p.tok))
+    lexMessage(p.lex, errIdentifierExpected, prettyTok(p.tok))
   
 proc ExpectIdent(p: TParser) = 
   if p.tok.tokType != tkSymbol: 
-    lexMessage(p.lex, errIdentifierExpected, tokToStr(p.tok))
+    lexMessage(p.lex, errIdentifierExpected, prettyTok(p.tok))
   
 proc Eat(p: var TParser, TokType: TTokType) = 
   if p.tok.TokType == TokType: getTok(p)

todo.txt

@@ -46,7 +46,6 @@ version 0.9.XX
 - generalized case statement (requires better transf)
 - tlastmod returns wrong results on BSD (Linux, MacOS X: works)
 - nested tuple unpacking
-- better error messages for used keywords as identifiers
 - case statement branches should support constant sets
 - 'nimrod def': does not always work
 - test branch coverage