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Function: ensure()

ensure\<T>(value, guard, options?): T

Validate a value and return it typed, or throw TypeError.

Use when you need the validated value as a typed return.

Type Parameters

T

T

Parameters

value

unknown

Value to validate

guard

Flame\<T>

Type guard to apply

options?

FlameOptions

Optional context for error messages

Returns

T

The same value as value, typed as T (no conversion is performed)

Throws

TypeError if the guard returns false

Example

TypeScript
const name = ensure(input, FlameGuards.isString, { at: "processRow", label: "name" });
Logger.log(name.toUpperCase()); // name is typed as string

Since

0.37.0