In the process of making an XML parser :
As the title suggests I have documented the rules as shown in my code below , but flex seems to miss a specific one.
Error : Cmd Error Img
The line in question is :
{boolean} {yylval.booleanval = strdup(yytext); if(err==1){printf("\t\t\t\t\t\t");}; return BOOLEAN;}```
When clearly declared flex seems to disregard it, where for the other rules no such problem arises.
Flex Code :
%option noyywrap
%option yylineno
string [_a-zA-Z][_a-zA-Z0-9]*
digit [0-9]
integer {digit}+
boolean "True" | "False"
text ({string}| )*
%%
. {printf("%s",yytext);}
{boolean} {yylval.booleanval = strdup(yytext); if(err==1){printf("\t\t\t\t\t\t");}; return BOOLEAN;}
{integer} {return INT;}
{string} {return STRING;}
%%
Rereading the question, I think there is a terminology problem. The rule is
{boolean} {yylval.booleanval = strdup(yytext); if(err==1){printf("\t\t\t\t\t\t");}; return BOOLEAN;}
Like all rule, that rule consists of *pattern" and an action. The pattern {boolean} consists only of a macro expansion. Once the macro is expanded, the line can no longer be recognised as a rule because of stray whitespace in the macro's definition, as I explained in the original answer below:
As indicated by the error message, the problem is the pattern in line 22 of your flex file, which contains a macro expansion of boolean:
boolean "True" | "False"
Flex patterns may not contain unquoted whitespace, whether entered directly or through a macro.
If you insist on using a macro, it could be:
boolean True|False
Although nothing prevents you from inserting the pattern directly in the rule:
True|False {yylval.booleanval = strdup(yytext); if(err==1){printf("\t\t\t\t\t\t");}; return BOOLEAN;}