chunk-on

array →
chunk-on(
    position: integer
) → tuple

Splits an array on a zero-based boundary and returns the elements before and from that position as a tuple. Positions beyond the end use the end boundary. Returns null when the position is negative or the input cannot be evaluated.

Parameters

Name	Type	Required	Description
position	integer	Yes	The zero-based boundary position; the element at this position belongs to the right chunk.

Argument evaluation

• position: Evaluated once in the enclosing context.

Behavior

chunk-on materializes the input and returns T(before, from-position). Positions beyond the input cardinality use the end boundary, so the right chunk is empty. Negative positions return null.

Examples

{10, 20, 30, 40} | chunk-on(2) → T({10, 20}, {30, 40})

Kind: Function
Scope: array/partitioning
Aliases: None