Re: Lex , Yacc Problem

Hello,


try to use an C array of type integer and an position
counter. Initialize the array element with 0 and parse the code. Each
time you parse a #if, evaluate it an set at array[positon counter] an
1 and increment the position counter. Next time you parse #if, check
the array[position counter minus 1] if it 1 and when, do nothing.
Each time you parse #endif, decrease position counter (minus 1) and
you can do a check, if array[position counter] is 1 (not execute) or 0
(execute).


symbolic code:.


int pos_counter = 0;
int if_array[2048] = { 0,0,0 .... };


parse_code()
{
    if (pos_counter > 0) {
        if (if_array[pos_counter - 1] == 1) { return; }
    }


    parse_code here
]


YACC:
parse_if
: '#' TOKEN_IF commands {
    pos_counter = pos_counter + 1;
}
;


commands
:
| '#' TOKEN_ENDIF { pos_counter = pos_counter - 1; }
| TOKEN_MOV {
    parse_code();
}
;


Cheers
Jens

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