Can I use @parallel for class/instance methods?

edit

This isn't quite an answer, but hopefully will help.

Niles, look at the traceback more carefully.

    114                 return self.p_iter(f, (normalize_input(a) for a in args[0]))
    115             else:
--> 116                 return f(*args, **kwds)
    117         return g
    118

Clearly it's gotten the parallel, as you say. But the whole thing is

# Construct the wrapper parallel version of the function we're wrapping.
# We may rework this so g is a class instance, which has the plus that
# we can query g for how it works, etc.
def g(*args, **kwds):
    if len(args) > 0 and isinstance(args[0], (list, types.GeneratorType)):
        return self.p_iter(f, (normalize_input(a) for a in args[0]))
    else:
        return f(*args, **kwds)
return g

If I insert a print statement (print args) before the if/else as well as print statements about which branch I take, I get

sage: T.meth1(L[0])
(<class '__main__.PTest'>, 1000)
second branch
168
sage: r = T.meth1(L)
(<class '__main__.PTest'>, [1000, 2000, 3000, 4000, 5000])
second branch
---------------------------------------------------------
TypeError

Does this help? It's never even reaching the point of the iterator, because the first item in args is not iterable, but the class itself. I don't know how to fix this, except by adding a case in the if statement, but I have no idea whether that would break anything else.

Here are some ideas for making the @parallel decorator usable on methods.

I did not check the code. But usually, a decorator takes as its argument a function f. Now, it is easy to check whether f is a plain function or a method: Use ismethod() or ismethoddescriptor() from the inspect module.

On top of that, one may even think of making @parallel usable on wrapped methods, such as

@parallel
@cached_method
def my_method(self, L,**args):

In that case, the function put into the @parallel decorator would be an instance of a CachedMethodCaller. Those things could be tested with the function isclassinstance() from sage.misc.sageinspect. Perhaps that particular example does not make sense, but it may still be a case to be taken into account.