Re: Implicit operator precedence

# When it came to implementing operator precedence, as a quick hack i
# worked out that instead of all the %left DIV MUL business, i could
# simply put the rules in order and resolve shift/reduce conflicts by
# the number of the rule. it's easier to explain through code:


Or you could use an archaic hack that doesn't involve introducing
ambiguities.


# expr: NUM { $$=$1; }
# | SUB expr { $$=-$2; }
# | expr EXP expr { $$=pow($1, $3); }
# | expr DIV expr { $$=$1/$3; }
# | expr MUL expr { $$=$1*$3; }
# | expr ADD expr { $$=$1+$3; }
# | expr SUB expr { $$=$1-$3; }
# | OPEN expr CLOSE { $$=$2; }
# ;


expr ::= expr1 | expr ADD expr1 | expr SUB expr1
expr1 ::= expr2 | expr1 MUL expr2 | expr1 DIV expr2
expr2 ::= expr3 | SUB expr2
expr3 ::= expr4 | expr4 EXP expr3
expr4 ::= NUM | OPEN expr CLOSE


--
SM Ryan http://www.rawbw.com/~wyrmwif/

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