From 40f97e49084e04f74f12dd9bccd05c9da11dd591 Mon Sep 17 00:00:00 2001 From: Adam Chlipala Date: Thu, 28 May 2015 10:23:43 -0400 Subject: Handling overflow in integer literals (contributed by Gabriel Riba) --- src/urweb.lex | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) (limited to 'src/urweb.lex') diff --git a/src/urweb.lex b/src/urweb.lex index e1ffd1c3..fcf10d94 100644 --- a/src/urweb.lex +++ b/src/urweb.lex @@ -182,7 +182,7 @@ cid = [A-Z][A-Za-z0-9_]*; ws = [\ \t\012\r]; intconst = [0-9]+; realconst = [0-9]+\.[0-9]*; -hexconst = 0x[0-9A-F]{1,8}; +hexconst = 0x[0-9A-F]+; notags = ([^<{\n(]|(\([^\*<{\n]))+; xcom = ([^\-]|(-[^\-]))+; oint = [0-9][0-9][0-9]; @@ -542,17 +542,25 @@ xint = x[0-9a-fA-F][0-9a-fA-F]; {id} => (Tokens.SYMBOL (yytext, pos yypos, pos yypos + size yytext)); {cid} => (Tokens.CSYMBOL (yytext, pos yypos, pos yypos + size yytext)); - {hexconst} => (case StringCvt.scanString (Int64.scan StringCvt.HEX) (String.extract (yytext, 2, NONE)) of + {hexconst} => (let val digits = String.extract (yytext, 2, NONE) + val v = (StringCvt.scanString (Int64.scan StringCvt.HEX) digits) + handle Overflow => NONE + in + case v of SOME x => Tokens.INT (x, pos yypos, pos yypos + size yytext) | NONE => (ErrorMsg.errorAt' (pos yypos, pos yypos) ("Expected hexInt, received: " ^ yytext); - continue ())); + continue ()) + end); - {intconst} => (case Int64.fromString yytext of + {intconst} => (let val v = (Int64.fromString yytext) handle Overflow => NONE + in + case v of SOME x => Tokens.INT (x, pos yypos, pos yypos + size yytext) | NONE => (ErrorMsg.errorAt' (pos yypos, pos yypos) ("Expected int, received: " ^ yytext); - continue ())); + continue ()) + end); {realconst} => (case Real64.fromString yytext of SOME x => Tokens.FLOAT (x, pos yypos, pos yypos + size yytext) | NONE => (ErrorMsg.errorAt' (pos yypos, pos yypos) -- cgit v1.2.3