Function Repository Resource:

AppendAt

Append to the specified element or after the last element at a specified level of an expression

Contributed by: Wolfram Staff

ResourceFunction["AppendAt"][expr,elem,level]

gives expr with elem appended to the end of the last expression at depth level.

ResourceFunction["AppendAt"][expr,elem,{k₁,k₂,…}]

appends elem to the part of expr at the position specified by indices k_i.

ResourceFunction["AppendAt"][assoc,elem,{key}]

appends elem to the value corresponding to the specified key in the association.

Details

ResourceFunction["AppendAt"][list,elem,1] is equivalent to Append[list,elem].

key can be a string or an arbitrary expression in the form Key[key].

Append to the last part of the expression at the specified level:

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Append to the element of the expression at the specified position:

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Append to the values at the specified string key in the association:

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Specify an arbitrary key:

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For List expressions, AppendAt at level 1 is equivalent to Append:

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