How to get the value of current ?

[david542542]

I've been having a bit of trouble getting the current string-value of a lex token. Here is what I'm currently doing:

from ExprGenerator import ExprGenerator
from grammarinator.runtime import *
import random

class MyExprGenerator(ExprGenerator):

    def __init__(self, **kwargs):
        super().__init__(**kwargs)

    def Int(self, parent=None):
        with RuleContext(self, UnlexerRule(name='Int', parent=parent)) as current:
            UnlexerRule(src=str(random.random()), parent=current)

            # such a hackish way to get the current value?
            _current_val = "{}".format(current)
            if float(_current_val) < 0.5: return self.Int(parent=parent)

            return current

Is there a better way to get current ? I tried a few things, but I was basically getting a parent/child node or None, for example:

>>> current.__dict__
# {'name': 'Int', 'parent': <grammarinator.runtime.tree.UnparserRule object at 0x107f0deb0>, 'children': [<grammarinator.runtime.tree.UnlexerRule object at 0x107f1ca90>], 'level': None, 'depth': None, 'src': None}

What's the suggested way to get the current value? What I'm trying to do is validation, for example, make sure a number is > 0.5, which is pretty difficult to do directly from the antlr grammar, so I'm doing some additional validation in the listeners/generators. Thanks so much for your time and help!

David

[renatahodovan]

If your only goal is to ensure that Int generates numbers bigger than 0.5, then there is a simpler way:

def Int(self, parent=None):
    with RuleContext(self, UnlexerRule(name='Int', parent=parent)) as current:
        UnlexerRule(src=str(random.random() + 0.5), parent=current)
        return current

If you like/need your approach then:

def Int(self, parent=None):
    with RuleContext(self, UnlexerRule(name='Int', parent=parent)) as current:
        value = UnlexerRule(src=str(random.random()), parent=current)
        if float(str(current)) < 0.5: return self.Int(parent=parent)
            # Or ...
            # if float(value.src) < 0.5: return self.Int(parent=parent)
            return current

[david542542]

@renatahodovan thanks so much that works. By the way, I sent you an email to your contact on Github about a few questions if that's ok -- thanks again for your help!