map

array →
map(
    transformation: expression
) → array

Applies a transformation expression to each input item and returns the transformed values. Preserves input cardinality (one output item per input item). Returns null when the input is not an enumerable or is a string.

Parameters

Name	Type	Required	Description
transformation	expression	Yes	Expression creating the transformation applied to each input item.

Argument evaluation

Visits each element of the array or each pair of the dictionary supplied as pipeline input to this map call, in enumeration order.

• transformation: Evaluated once per visited element, with that element as its context. For dictionary input, $key and $value resolve to the key and value of the visited pair, rather than a surrounding record.

Behavior

Dictionaries participate directly as ordered collections of first-class pairs. Keys and values are preserved without coercion. The result is an ordinary array, and an empty dictionary produces an empty array. Records require pairs to expose their fields as pairs.

Examples

{1, 2, 3} | map(add(1)) → {2, 3, 4}
!{"BE" => 100, "FR" => 80} | map(tuple($key, $value)) → {T("BE", 100), T("FR", 80)}

Kind: Function
Scope: array
Aliases: map