Re: Please assist: if/else condition problem with lex/yacc

paktsardines@gmail.com (Pakt) wrote:
"
if_else_block:
                    TOK_IF expression LBRACE commands RBRACE TOK_ELSE LBRACE commands
RBRACE {
                                    if ($2 == true) {
                                                    $$=$4;
                                    }
                                    else {
                                                    $$=$8;
                                    }
                    }
                    ;
"
I suppose this will not work as you wish. Actually, yacc will parse
the two "commands" above, but not parse one of them by the
"expression". The simple solution is to set a global flag to indicate
the "expression" result, and when you interpret "command", you can
check the flag to do your special things.


Kevin Lynx
[A flag will work for if/then/else, but I still encourage people to turn
anything they plan to interpret into an AST first. Flags won't help
when you want to add loops. -John]

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