using `int` as Wildcard about matchpy

[wheerd]

I am not sure why you would want to have a constant wildcard. The whole point of wildcards is that they do match anything, not just a constant value. You can use any Symbol or ConstantSymbol in a pattern as well. Your code works fine for me, too. A traceback or some code of what you are trying to use the ConstantWild for would be helpful. If you want a wildcard, that can only match constants, you can use the SymbolWildcard class or just a = Wildcard.symbol('a', ConstantSymbol).

[arihantparsoya]

When I have a pattern(Which uses ConstantSymbol):

And(FreeQ(m_, x_), NonzeroQ(Add(ConstantSymbol(1), m_)))

and I want to substitute variables. I am receiving errors:

  File "/users/parsoyaarihant/sympy/sympy/rubi/tests/test_rubi.py", line 8, in test_rubi_integrate
    print(rubi_integrate(expr, x))
  File "/Users/parsoyaarihant/sympy/sympy/rubi/rubi.py", line 17, in rubi_integrate
    rubi = rubi_object()
  File "/Users/parsoyaarihant/sympy/sympy/rubi/patterns.py", line 40, in rubi_object
    rubi.add(rule2)
  File "/Users/parsoyaarihant/anaconda/lib/python3.6/site-packages/matchpy-0.3.1-py3.6.egg/matchpy/matching/many_to_one.py", line 730, in add
    self.matcher.add(rule.pattern, rule.replacement)
  File "/Users/parsoyaarihant/anaconda/lib/python3.6/site-packages/matchpy-0.3.1-py3.6.egg/matchpy/matching/many_to_one.py", line 330, in add
    self._internal_add(pattern, label, renaming)
  File "/Users/parsoyaarihant/anaconda/lib/python3.6/site-packages/matchpy-0.3.1-py3.6.egg/matchpy/matching/many_to_one.py", line 346, in _internal_add
    renamed_constraints = [c.with_renamed_vars(renaming) for c in pattern.local_constraints]
  File "/Users/parsoyaarihant/anaconda/lib/python3.6/site-packages/matchpy-0.3.1-py3.6.egg/matchpy/matching/many_to_one.py", line 346, in <listcomp>
    renamed_constraints = [c.with_renamed_vars(renaming) for c in pattern.local_constraints]
  File "/Users/parsoyaarihant/sympy/sympy/rubi/constraint.py", line 22, in with_renamed_vars
    copy = cons(self.expr.with_renamed_vars(renaming), [])
  File "/Users/parsoyaarihant/anaconda/lib/python3.6/site-packages/matchpy-0.3.1-py3.6.egg/matchpy/expressions/expressions.py", line 592, in with_renamed_vars
    variable_name=renaming.get(self.variable_name, self.variable_name)
  File "/Users/parsoyaarihant/anaconda/lib/python3.6/site-packages/matchpy-0.3.1-py3.6.egg/matchpy/expressions/expressions.py", line 591, in <genexpr>
    *(o.with_renamed_vars(renaming) for o in self.operands),
  File "/Users/parsoyaarihant/anaconda/lib/python3.6/site-packages/matchpy-0.3.1-py3.6.egg/matchpy/expressions/expressions.py", line 592, in with_renamed_vars
    variable_name=renaming.get(self.variable_name, self.variable_name)
  File "/Users/parsoyaarihant/anaconda/lib/python3.6/site-packages/matchpy-0.3.1-py3.6.egg/matchpy/expressions/expressions.py", line 591, in <genexpr>
    *(o.with_renamed_vars(renaming) for o in self.operands),
  File "/Users/parsoyaarihant/anaconda/lib/python3.6/site-packages/matchpy-0.3.1-py3.6.egg/matchpy/expressions/expressions.py", line 592, in with_renamed_vars
    variable_name=renaming.get(self.variable_name, self.variable_name)
  File "/Users/parsoyaarihant/anaconda/lib/python3.6/site-packages/matchpy-0.3.1-py3.6.egg/matchpy/expressions/expressions.py", line 591, in <genexpr>
    *(o.with_renamed_vars(renaming) for o in self.operands),
  File "/Users/parsoyaarihant/anaconda/lib/python3.6/site-packages/matchpy-0.3.1-py3.6.egg/matchpy/expressions/expressions.py", line 667, in with_renamed_vars
    return type(self)(self.name, variable_name=renaming.get(self.variable_name, self.variable_name))
TypeError: __init__() got an unexpected keyword argument 'variable_name'

This does not happen if I use a Wildcard.dot object instead of ConstantSymbol.

[arihantparsoya]

On side note, the documentation website for MatchPy doesn't seems to be working properly. I dont see any documentation on this website:

http://matchpy.readthedocs.io/en/latest/api/matchpy.expressions.expressions.html

[wheerd]

Oh, thanks for the hint. I thought I had fixed the doc building process, but apparently it was still broken.
Now it should be fixed, you might need to refresh the page to see the new version.

[wheerd]

The problem is that your ConstantSymbol inherits from Symbol, but changes the __init__ signature.
The __init__ method needs to accept the variable_name keyword:

class ConstantSymbol(Symbol):
    ...
    def __init__(self, name: str, variable_name=None) -> None:
        ...

[arihantparsoya]

This is the code for ConstantSymbol(updated) but I am still getting the same error:

class ConstantSymbol(Symbol):
    def __init__(self, value):
        super(self.__class__, self).__init__(name=str(value), variable_name=None)
        self.value = value

[wheerd]

Try this instead:

class ConstantSymbol(Symbol):
    def __init__(self, value, variable_name=None):
        super(self.__class__, self).__init__(name=str(value), variable_name=variable_name)
        self.value = value

[arihantparsoya]

It works. Thanks!

Can you explain what was wrong with the previous implementation?

[wheerd]

When renaming the variables in the expression, the new Expression is created with type(expr)(..., variable_name='new_name'). In this example, the new symbol is created with ConstantSymbol(..., variable_name='new_name'), but the __init__ does not accept variable_name. Now that I think about it, you should probably override with_renamed_vars in your ConstantSymbol class, so that the value property is set correctly.