Passing Multiple Arguments To Pool.map Using Class Function

I'm trying to thread as described in this post, and also pass multiple arguments in Python 2.7 through a work-around described here. Right now I have something like this, a functi

Solution 1:

itertools.izip(username*len(self.repo_list),itertools.repeat(self.repo_list)) yields a tuple.

You need to pass 2 arguments explicitly to your method (self is implicitly passed because it's a non-static method), but you only pass 1 tuple explicitly, plus the implicit self which makes 2 arguments, hence the confusing error message.

You have to use * to pass your tuple as 2 separate arguments, like this:

master_list = pool.map(self.length_scraper2,
     *itertools.izip(username*len(self.repo_list),itertools.repeat(self.repo_list)))

simple test using the classical map on a simple function:

def function(b,c):
    return (b,c)

print(list(map(function,zip([1,2],[4,5]))))

error:

print(list(map(function,zip([1,2],[4,5]))))
 TypeError: function() missing 1 required positional argument: 'c'

now adding single asterisk to expand args:

print(list(map(function,*zip([1,2],[4,5]))))

works:

[(1, 2), (4, 5)]

same goes for class method:

classFoo:
    deffunction(self,b,c):
        return (b,c)

f = Foo()

print(list(map(f.function,*zip([1,2],[4,5]))))