Type Alias: Flame\<T>¶

Flame\<T> = (value) => value is T

Type guard function signature for runtime type checking.

A Flame<T> is a function that narrows unknown to T. Returns true if the value matches the expected type, false otherwise.

The Flame name is the root of the library's naming convention — FlameFrame carries a Flame schema, while BareFrame does not.

Type Parameters¶

T¶

T = unknown

Parameters¶

value¶

unknown

Returns¶

value is T

Example¶

TypeScript

const isString: Flame<string> = (v): v is string => typeof v === "string";

if (isString(value)) {
  Logger.log(value.toUpperCase()); // value is typed as string
}

Since¶

0.37.0