nix-config/lib/attrs.nix

58 lines
1.4 KiB
Nix

{ lib, ... }:
let
inherit (lib)
filterAttrs
foldl
listToAttrs
mapAttrs'
nameValuePair
recursiveUpdate
;
in
{
# Filter a generated set of attrs using a predicate function.
#
# mapFilterAttrs ::
# (name -> value -> bool)
# (name -> value -> { name = any; value = any; })
# attrs
mapFilterAttrs = pred: f: attrs: filterAttrs pred (mapAttrs' f attrs);
# Generate an attribute set by mapping a function over a list of values.
#
# genAttrs' ::
# [ values ]
# (value -> { name = any; value = any; })
# attrs
genAttrs' = values: f: listToAttrs (map f values);
# Merge a list of attrs non-recursively, later values override previous ones.
#
# merge ::
# [ attrs ]
# attrs
merge = foldl (a: b: a // b) { };
# Merge a list of attrs recursively, later values override previous ones.
#
# recursiveMerge ::
# [ attrs ]
# attrs
recursiveMerge = foldl recursiveUpdate { };
# Rename each of the attributes in an attribute set using the mapping function
#
# renameAttrs ::
# (name -> new name)
# attrs
renameAttrs = f: mapAttrs' (name: value: nameValuePair (f name) value);
# Rename each of the attributes in an attribute set using a function which
# takes the attribute's name and value as inputs.
#
# renameAttrs' ::
# (name -> value -> new name)
# attrs
renameAttrs' = f: mapAttrs' (name: value: nameValuePair (f name value) value);
}