Function Repository Resource:

NestedKeyDrop

Source Notebook

Drop keys from a nested association

Contributed by: Robert Ferguson

ResourceFunction["NestedKeyDrop"][assoc,{key}]

returns assoc with key dropped.

ResourceFunction["NestedKeyDrop"][assoc,{key₁,…,key_m}]

returns assoc with key_m dropped deep in the association.

ResourceFunction["NestedKeyDrop"][assoc,{{key_1,1,…,key_1,m},{key_2,1,…,key_2,n},…}]

returns assoc with the key specified by each key sequence dropped deep in the association.

ResourceFunction["NestedKeyDrop"][{assoc₁,assoc_2,…},…]

returns a list of associations with keys dropped in each, as specified in the given key sequence(s).

Details and Options

ResourceFunction["NestedKeyDrop"] preserves the original order of elements.

Any key that does not appear in the given association is ignored.

Where a key is a list, it must be given as Key[list].

The form of the specified keys is as in certain built-in functions such as Lookup, in that the outermost Key in Key[key] is stripped. This is different from other built-in functions such as Append and KeyExistsQ, where the function interprets the key as it is literally given.

All key-value pairs in the nested association should be associated using Rule. Any use of RuleDelayed may cause erroneous behaviour.

ResourceFunction["NestedKeyDrop"] can only be applied to associations.