Hang if recursion about mpc HOT 5 CLOSED

Hey,

Looks like your grammar is left-recursive in some situations when parsing item. The first part of item is factor. If factor then fails for all options before item it will try to match an item. In matching an item it will look for a factor and the loop will continue.

mpc can't detect left-recursion so you will have to change your grammar manually. I can't tell just from looking at it how to make it right-recursive but there is probably some simple transformation to be made.

Thanks,

Dan

from mpc.

OK, I solved this issue.

https://github.com/mattn/orelang/blob/master/ore.c#L40

Thanks.

from mpc.

Great! No problem.

from mpc.

Ah, however it still have problem for future. For example I may want to implement anonymous function call like below.

var counter = func() {
  var c = 0;
  return func() {
    c++;
    return c;
  };
}();

So, yacc stracture should be below.

call : <factor> '(' <factor>? (',' <factor>)* ')' ;

This make recursible.

from mpc.

I don't know the solution to this without thinking about it much more, but I think perhaps you can fix it by instead of making a call a type of factor, instead adding the parenthesis calling syntax as an optional part of those factors which support function calls.

Perhaps in the future I can add some code to detect or refactor Left Recursion but for now I think you will have to work out these issues yourself :)

from mpc.