[pypy-dev] rffi strict typing

[Simon Burton]

The lltype's are very strict about types.
If I declare an llexternal that takes a Float arg,
I cannot call it with an int arg. Well maybe that's
not so bad. But in rlib.rsdl there are functions that take
Unsigned, and these don't work even if called with
a non-negative constant int... Can we loosen up
these restrictions ? Maybe put an "is_compatable(self, other)"
method on LowLevelType's ?

Simon.

using py lib: /home/simon/local/pypy-latest/py <rev 45205>

test/test_SDL.py[2] FF

__________________________________________________________________________________________________________________________________________________________________________________________________________ entrypoint: test_run ____________________________________________________________
    def test_run():
>       demo()

[/home/simon/local/pypy-latest/pypy/rlib/rsdl/test/test_SDL.py:48]
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    def demo():

>       if SDL.Init(SDL.INIT_VIDEO) < 0:

[/home/simon/local/pypy-latest/pypy/rlib/rsdl/test/test_SDL.py:13]
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

    def __call__(self, *args):
        if isinstance(self._T, FuncType):
            if len(args) != len(self._T.ARGS):
                raise TypeError,"calling %r with wrong argument number: %r" % (self._T, args)
            for a, ARG in zip(args, self._T.ARGS):
                if typeOf(a) != ARG:
E                   raise TypeError,"calling %r with wrong argument types: %r" % (self._T, args)
>                   TypeError: calling <Func ( Unsigned ) -> Signed> with wrong argument types: (32,)

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