gleam/function

compose

pub fn compose(fun1: fn(a) -> b, fun2: fn(b) -> c) -> fn(a) -> c

Takes two functions and chains them together to form one function that takes the input from the first and returns the output of the second.

constant

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pub fn constant(value: a) -> fn(b) -> a

Takes a single argument and returns a new function that ignores its argument and always returns the input value.

curry2

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pub fn curry2(fun: fn(a, b) -> c) -> fn(a) -> fn(b) -> c

Takes a function with arity two and returns a curried equivalent. fn(a, b) -> c becomes fn(a) -> fn(b) -> c.

curry3

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pub fn curry3(fun: fn(a, b, c) -> d) -> fn(a) ->
  fn(b) -> fn(c) -> d

Takes a function with arity three and returns a curried equivalent. fn(a, b, c) -> d becomes fn(a) -> fn(b) -> fn(c) -> d.

curry4

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pub fn curry4(fun: fn(a, b, c, d) -> e) -> fn(a) ->
  fn(b) -> fn(c) -> fn(d) -> e

Takes a function with arity four and returns a curried equivalent.

curry5

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pub fn curry5(fun: fn(a, b, c, d, e) -> f) -> fn(a) ->
  fn(b) -> fn(c) -> fn(d) -> fn(e) -> f

Takes a function with arity five and returns a curried equivalent.

curry6

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pub fn curry6(fun: fn(a, b, c, d, e, f) -> g) -> fn(a) ->
  fn(b) -> fn(c) -> fn(d) -> fn(e) -> fn(f) -> g

Takes a function with arity six and returns a curried equivalent.

flip

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pub fn flip(fun: fn(a, b) -> c) -> fn(b, a) -> c

Takes a function that takes two arguments and returns a new function that takes the same two arguments, but in reverse order.

identity

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pub fn identity(x: a) -> a

Takes a single argument and always returns its input value.

tap

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pub fn tap(arg: a, effect: fn(a) -> b) -> a

Takes an argument and a single function, calls that function with that argument and returns that argument instead of the function return value. Useful for running synchronous side effects in a pipeline.

gleam_stdlib - v0.23.0

Functions