X-partial

More powerful partial application with the X object

pipetools.xpartial(func, *xargs, **xkwargs)

Like functools.partial(), but can take an XObject placeholder that will be replaced with the first positional argument when the partially applied function is called.

Useful when the function’s positional arguments’ order doesn’t fit your situation, e.g.:

>>> reverse_range = xpartial(range, X, 0, -1)
>>> reverse_range(5)
[5, 4, 3, 2, 1]

It can also be used to transform the positional argument to a keyword argument, which can come in handy inside a pipe:

xpartial(objects.get, id=X)

Also the XObjects are evaluated, which can be used for some sort of destructuring of the argument:

xpartial(somefunc, name=X.name, number=X.contacts['number'])

Lastly, unlike functools.partial(), this creates a regular function which will bind to classes (like the curry function from django.utils.functional).

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