forwardAsserts

The forwardAsserts() function validates an input with a predicate, throws when it fails, and returns the validated value. It supports classic and curried forms.

Interactive example

Syntax

Classic signatures

function forwardAsserts<
	GenericInput extends unknown,
	GenericPredicate extends GenericInput
>(
	input: GenericInput,
	predicate: (input: GenericInput) => input is GenericPredicate
): GenericPredicate;

function forwardAsserts<
	GenericInput extends unknown
>(
	input: GenericInput,
	predicate: (input: GenericInput) => boolean
): GenericInput;

Curried signatures

function forwardAsserts<
	GenericInput extends unknown,
	GenericPredicate extends GenericInput
>(
	predicate: (input: GenericInput) => input is GenericPredicate
): (input: GenericInput) => GenericPredicate;

function forwardAsserts<
	GenericInput extends unknown
>(
	predicate: (input: GenericInput) => boolean
): (input: GenericInput) => GenericInput;

Parameters

• input: The value to validate in direct mode.
• predicate: A boolean predicate or type guard used to validate the input.

Return value

Returns the validated input. With a type guard predicate, the returned type is narrowed. With a boolean predicate, the original input type is preserved. Throws an AssertsError when validation fails.

See also

• asserts - Throws on failure without returning the validated value
• isType - Builds runtime type guards
• pipe - Chains the curried form inside a pipeline