functoolz

Functions –

• apply(*func_and_args, **kwargs) – It simply applies a function and returns the result.

  
  

  
  
  

  import toolz       def double(n):     return n + n    print(toolz.functoolz.apply(double, 2))

  Output –

  4
  

• complement(func) – As its name suggests, it converts returns the logical complement of the input provided.

  
  

  
  
  

  import toolz       def is_mulitple_of_5(n):     return n % 5 == 0    not_multiple_of_5 = toolz.functoolz.complement(is_mulitple_of_5)    print(is_mulitple_of_5(10)) print(not_multiple_of_5(10))

  Output –

  True
  False
  

• compose(*funcs) – It returns a function that applies other functions in sequence. Functions are applied from right to left. If no arguments are provided, the identity function (f(x) = x) is returned.

  
  

  
  
  

  import toolz       def func(n):     return n + n    def square(n):     return n * n    x = toolz.functoolz.compose(func, square)(3) print(x)

  Output –

  18
  

• compose_left(*funcs) – It returns a function that applies other functions in sequence. Functions are applied from left to right. If no arguments are provided, the identity function (f(x) = x) is returned.

  
  

  
  
  

  import toolz       def func(n):     return n + n    def square(n):     return n * n    x = toolz.functoolz.compose_left(func, square)(3) print(x)

  Output –

  36
  

• flip – Call the function with the arguments in reverse order.

  
  

  
  
  

  import toolz       def mod(a, b):     return a % b    print('7 % 3 :', toolz.functoolz.flip(mod, 3, 7))

  Output –

  7 % 3 : 1
  

• identity(x) – Identity function, simply returns x.

  
  

  
  
  

  import toolz       print(toolz.functoolz.identity(6))

  Output –

  6
  

• pipe(data, *funcs) – Pipe a value through a sequence of functions. It is equivalent to compose_left(*funcs)

  
  

  
  
  

  import toolz       print(toolz.functoolz.pipe(3, double, square))

  Output –

  36
  

• thread_first(val, *forms) – Thread value through a sequence of functions/forms.

  
  

  
  
  

  import toolz       def mod(a, b):     return a % b    def double(n):     return n + n    print(toolz.functoolz.thread_first(3, (mod, 2), double))

  Output –

  2
  

• thread_last(val, *forms) – Thread value through a sequence of functions/forms.

  
  

  
  
  

  import toolz       def mod(a, b):     return a % b    def double(n):     return n + n    print(toolz.functoolz.thread_last(3, (mod, 2), double))

  Output –

  4
  

Toolz package provides a set of utility functions for iterators, functions, and dictionaries. These functions extend the standard libraries itertools and functools and borrow heavily from the standard libraries of contemporary functional languages. This package consists of following modules –

• dicttoolz
• functoolz
• itertoolz
• recipes
• sandbox