pipe

lib.trivial.pipe

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Pipes a value through a list of functions, left to right.

Inputs

value: Value to start piping.
fns: List of functions to apply sequentially.

Type

pipe :: a -> [<functions>] -> <return type of last function>

Examples

`lib.trivial.pipe` usage example

pipe 2 [
    (x: x + 2)  # 2 + 2 = 4
    (x: x * 2)  # 4 * 2 = 8
  ]
=> 8

# ideal to do text transformations
pipe [ "a/b" "a/c" ] [

  # create the cp command
  (map (file: ''cp "${src}/${file}" $out\n''))

  # concatenate all commands into one string
  lib.concatStrings

  # make that string into a nix derivation
  (pkgs.runCommand "copy-to-out" {})

]
=> <drv which copies all files to $out>

The output type of each function has to be the input type
of the next function, and the last function returns the
final value.