Re: Grammar with low-precedence postfix operator?

On 2015-02-08, Stefan Monnier <monnier@iro.umontreal.ca> wrote:
>> term
>> : INT
>> | '(' expr ')' //parentheses
>> | <assoc=right> term '^' term //exponentiation
>> | term term //implicit multiplication
>> ;
>
>> expr
>> : term
>> | ('+' | '-') expr //unary plus/minus
>> | expr ('/' | '*') expr //division and explicit multiplication
>> | expr ('+' | '-') expr //addition/subtraction
>> | expr '++' //increment
>> ;
>
> This last production rule is wrong: "expr ++" should produce a "term", not
> an "expr".


If that is so, then ++ shall not have the desired low precedence.


For instance a ^ b ++ be parsed as the exponentiation of two terms,
a and b++, not as ++ applied to the expression a ^ b, as desired.


[Oops, looks like you're right. -John]

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