diff --git a/c/lexer.l b/c/lexer.l
index 550ad85d..4acb026a 100644
--- a/c/lexer.l
+++ b/c/lexer.l
@@ -16,7 +16,7 @@
 "."|"="|";"|"["|"]"|","|":"|"("|")"|"{"|"}"|"|"|"+"|"\$" { return yytext[0];}
 
 \"(\\.|[^\\"])*\" |
-[+-]?[0-9.]+([eE][+-]?[0-9]+)? { 
+-?[0-9.]+([eE][+-]?[0-9]+)? { 
    yylval->literal = jv_parse_sized(yytext, yyleng); return LITERAL; 
 }