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Merge pull request #134969 from polykernel/setattrsbypath-patch

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lib: optimize setAttrByPath and cleaup imports
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Robert Hensing 2021-08-24 00:38:30 +02:00 committed by GitHub
parent 098ca1a9aa 3f4ce46a47
commit 9a775bf778
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1 changed files with 9 additions and 6 deletions
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15
lib/attrsets.nix
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@ -5,7 +5,7 @@ let
inherit (builtins) head tail length;
inherit (lib.trivial) and;
inherit (lib.strings) concatStringsSep sanitizeDerivationName;
inherit (lib.lists) fold foldr concatMap concatLists;
inherit (lib.lists) foldr foldl' concatMap concatLists elemAt;
in
rec {
@ -55,10 +55,13 @@ rec {
=> { a = { b = 3; }; }
*/
setAttrByPath = attrPath: value:
if attrPath == [] then value
else listToAttrs
[ { name = head attrPath; value = setAttrByPath (tail attrPath) value; } ];
let
len = length attrPath;
atDepth = n:
if n == len
then value
else { ${elemAt attrPath n} = atDepth (n + 1); };
in atDepth 0;
/* Like `attrByPath' without a default value. If it doesn't find the
path it will throw.
@ -195,7 +198,7 @@ rec {
]
*/
cartesianProductOfSets = attrsOfLists:
lib.foldl' (listOfAttrs: attrName:
foldl' (listOfAttrs: attrName:
concatMap (attrs:
map (listValue: attrs // { ${attrName} = listValue; }) attrsOfLists.${attrName}
) listOfAttrs