function

FP tools for functions

FP utilities to manipulate and partially apply functions.

• function swap - Swap the arguments of a 2 argument function

• function compose - Function composition

• function negate - Transforms a predicate to its negation

• function sequenced - Convert function to take a sequence of its arguments

• function partial - Returns a partially applied function

pythonic_fp.fptools.function.swap(f: Callable[[U, V], R]) → Callable[[V, U], R]

swap

Swap arguments of a two argument function.

param f:

Two argument function.

returns:

A version of f with its arguments swapped.

pythonic_fp.fptools.function.compose(f: Callable[[D], T], g: Callable[[T], R]) → Callable[[D], R]

compose

Function Composition

param f:

Function called first with domain D and range T.

param g:

Function called on result with domain T and range R.

returns:

The composite function g∘f(d) = g(f(d))

pythonic_fp.fptools.function.negate(f: Callable[[P], bool]) → Callable[[P], bool]

negate

Take a predicate and return its negation.

param f:

a function f which returns a bool

returns:

the function not f

pythonic_fp.fptools.function.sequenced(f: Callable[[...], R]) → Callable[[tuple[Any]], R]

sequenced

Convert a function with arbitrary positional arguments to one taking a tuple of the original arguments.

param f:

Function with just positional parameters

returns:

An equivalent function taking a tuple of the arguments to f.

pythonic_fp.fptools.function.partial(f: Callable[[P], R], *args: Any) → Callable[[...], R]

partial

Partially apply arguments to a function with positional arguments left to right.

param f:

Function with just positional arguments.

param args:

Arguments to partially apply to f.

Warning

The types of the arguments are lost.

Tip

Best practice is to cast the result if it is not consumed immediately.