Rule precedence issue with grako

Question

I\'m redoing a minilanguage I originally built on Perl (see Chessa# on github), but I\'m running into a number of issues when I go to apply semantics.

Here is the gr

Answer 1

In Perl, you can use Marpa, a general BNF parser, which supports generalized precedence with associativity (and many more) out of the box, e.g.

:start ::= Script
Script ::= Expression+ separator => comma
comma ~ [,]
Expression ::=
    Number bless => primary
    | '(' Expression ')' bless => paren assoc => group
   || Expression '**' Expression bless => exponentiate assoc => right
   || Expression '*' Expression bless => multiply
    | Expression '/' Expression bless => divide
   || Expression '+' Expression bless => add
    | Expression '-' Expression bless => subtract

Full working example is here. As for programming languages, there is a C parser based on Marpa.

Hope this helps.