--- a/src/urweb.lex	Sun Jul 19 19:03:11 2015 -0700
+++ b/src/urweb.lex	Sun Jul 19 19:05:16 2015 -0700
@@ -178,11 +178,11 @@
 
 id = [a-z_][A-Za-z0-9_']*;
 xmlid = [A-Za-z][A-Za-z0-9_-]*;
-cid = [A-Z][A-Za-z0-9_]*;
+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];
@@ -537,22 +537,34 @@
 
 <INITIAL> "CURRENT_TIMESTAMP" => (Tokens.CURRENT_TIMESTAMP (pos yypos, pos yypos + size yytext));
 
-<INITIAL> "CURRENT_TIMESTAMP" => (Tokens.CURRENT_TIMESTAMP (pos yypos, pos yypos + size yytext));
+<INITIAL> "_LOC_" => (let val strLoc = ErrorMsg.spanToString (ErrorMsg.spanOf
+                                            (pos yypos, pos yypos + size yytext))
+                      in
+                          Tokens.STRING (strLoc, pos yypos, pos yypos + size yytext)
+                      end);
 
 <INITIAL> {id}        => (Tokens.SYMBOL (yytext, pos yypos, pos yypos + size yytext));
 <INITIAL> {cid}       => (Tokens.CSYMBOL (yytext, pos yypos, pos yypos + size yytext));
 
-<INITIAL> {hexconst}  => (case StringCvt.scanString (Int64.scan StringCvt.HEX) (String.extract (yytext, 2, NONE)) of
+<INITIAL> {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);
 
-<INITIAL> {intconst}  => (case Int64.fromString yytext of
+<INITIAL> {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);
 <INITIAL> {realconst} => (case Real64.fromString yytext of
                             SOME x => Tokens.FLOAT (x, pos yypos, pos yypos + size yytext)
                           | NONE   => (ErrorMsg.errorAt' (pos yypos, pos yypos)