let

any →
let(
    ...bindings: entry
) → any

Evaluates named bindings once and preserves the pipeline input for subsequent stages.

Parameters

Name	Type	Required	Description
bindings	entry	Variadic (one or more)	One or more named expressions whose results become lexical values.

Argument evaluation

• bindings: Evaluated once in declaration order against the original input supplied to this let call, stopping on failure. All expressions use the enclosing named-value environment; bindings from this call become visible together after every expression succeeds.

Behavior

Returns the original input unchanged, preserving its type. Reference computed values with @name, including null values. Bindings remain visible through subsequent pipeline stages and grouping parentheses in this expression invocation; nested inline invocations inherit them, may shadow them, and restore outer values on success or failure. This call adds no expression-root scope and does not change caret depth. Consecutive let calls support dependent bindings. At least one unquoted identifier assignment is required; duplicate names, positional entries, and spread are rejected. Unknown references use the normal unresolved-variable diagnostic. Unlike :>, which captures invocation input, let captures computed values; unlike with, it neither constructs a temporary record nor invokes a body. Bindings may shadow context variables without mutating them. Independently invoked expressions retain their own environment; caller values must be passed explicitly to named expressions when that invocation feature is available.

Examples

10 | let(double := multiply(2)) | add(1) → 11
10 | let(double := multiply(2)) | add(@double) → 30
{quantity := 4, unit-price := 5} | let(total := .quantity | multiply(.unit-price)) | @total → 20

Kind: Function
Scope: flow
Aliases: None