Hi,
I'm trying to write a grammar file for parsing expressions. The main part
goes as following:
%left '-' '+';
expr: expr '+' expr
| expr '-' expr
// Other operators...
| expr expr
| const
| id
;
"expr expr" here is function application, former expr is the function and
latter expression is an argument (as in Haskell).
What I need is function application having maximum priority and left
associativity. For some reason default behavior is the exact opposite:
minimum priority and right associativity.
So the first thing I've tried was declaring "%left APPLY;" and then adding
"%prec APPLY" to the corresponding line.
However, that changed nothing.
I was able to sort the problem with priority out by introducing new
non-terminal (just like priorities are handled in recursive parsers), but
associativity is still a problem here.
I don't understand what is wrong with %prec as documentation says it assigns
precedence to rule.
So can I be missing something fundamental about operator precedence in
bison?
Any other pointers how to get the desired behavior?
-- Regards, Petr.
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