pipeline.py

"""
Misc tools/functions written by Ross Delinger
"""


def assemblePipeLine(*args, **kwargs):
    """
    Given an arbitrary number of functions we create a pipeline where the output
    is piped between functions. you can also specify a tuple of arguments that
    should be passed to functions in the pipeline. The first arg is always the
    output of the previous function.
    """
    def wrapper(*data):
        if len(args) == 1:
            if args[-1].__name__ in kwargs:
                otherArgs = data + kwargs[args[-1].__name__]
                return args[-1](*otherArgs)
            else:
                return args[-1](*data)
        else:
            if args[-1].__name__ in kwargs:
                otherArgs = kwargs[args[-1].__name__]
                del kwargs[args[-1].__name__]
                return args[-1](assemblePipeLine(*args[:-1], **kwargs)(*data), *otherArgs)
            else:
                return args[-1](assemblePipeLine(*args[:-1], **kwargs)(*data))
    return wrapper


def testAssemblePipelineWithArgs():
    def add1(input_):
        return input_ + 1

    def subX(input_, x):
        return input_ - x

    def stringify(input_):
        return str(input_)

    pipeline = assemblePipeLine(
        add1,
        subX,
        stringify,
        subX=(2,),
        )
    print pipeline(10)