★ guardFalse()


Guards the provided value to be false.

const guardFalse = <Payload extends object>(
  value: false,
  callback?: ResultCallback<false, Payload>,
  payload?: Payload
): value is false => isFalse(value, callback, payload);

Code on GitHub

Generic type variables


The Payload generic type variable constrained by object indicates the type of optional parameter payload of the supplied callback function and payload optional parameter of the guardFalse() function from which it captures its value.


value: false

The value of false type to guard.

callback?: ResultCallback<false, Payload>

The optional callback function of ResultCallback type with parameters, the value that has been checked, the result of this check, and payload of generic type variable Payload with optional properties from the provided payload, to handle them before the result return. By default, it uses resultCallback() function.

payload?: Payload

An optional object of the generic type variable Payload is assigned to the payload of the given callback function.

Return type

value is false

The return type is a boolean as the result of its statement value is false.


The return value is a boolean indicating whether the value is a boolean type or an instance of Boolean equal to false.

Example usage

// Example usage.
import { guardFalse } from '@angular-package/type';

const valTrue = true as any;
const valFalse = false;

guardFalse(valTrue); // false, value is false
guardFalse(valFalse); // true, value is false
guardFalse(new Boolean(valTrue) as any); // false, value is false
guardFalse(new Boolean(valFalse) as any); // true, value is false

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