crossLists

lib.lists.crossLists

Docs pulled from | This Revision | about 1 hour ago

Return the image of the cross product of some lists by a function.

Examples

`lib.lists.crossLists` usage example

crossLists (x: y: "${toString x}${toString y}") [[1 2] [3 4]]
=> [ "13" "14" "23" "24" ]

The following function call is equivalent to the one deprecated above:

mapCartesianProduct (x: "${toString x.a}${toString x.b}") { a = [1 2]; b = [3 4]; }
=> [ "13" "14" "23" "24" ]

Noogle detected

Aliases

lib.crossLists

Implementation

The following is the current implementation of this function.

crossLists = warn
    ''lib.crossLists is deprecated, use lib.mapCartesianProduct instead.

    For example, the following function call:

    nix-repl> lib.crossLists (x: y: x+y) [[1 2] [3 4]]
    [ 4 5 5 6 ]

    Can now be replaced by the following one:

    nix-repl> lib.mapCartesianProduct ({x,y}: x+y) { x = [1 2]; y = [3 4]; }
    [ 4 5 5 6 ]
    ''
    (f: foldl (fs: args: concatMap (f: map f args) fs) [f]);