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  • isTrue()
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  1. is

★ isTrue()

PreviousisSymbol()NextisType()

Last updated 3 years ago

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isTrue()

Checks if value is a type or an instance of (by using the ) equal to true.

is-true.func.ts
const isTrue = <Payload extends object>(
  value: any,
  callback: ResultCallback<any, Payload> = resultCallback,
  payload?: Payload
): value is true =>
  callback(isBoolean(value) ? value.valueOf() === true : false, value, payload);

Generic type variables

Payloadextendsobject

The Payload generic type variable constrained by indicates the type of optional parameter of the supplied function and optional parameter of the function from which it captures its value.

Parameters

value: any

The value of type to check.

callback: ResultCallback<any, Payload>

payload?: Payload

Return type

value is true

Returns

Example usage

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

isTrue(false); // Returns `false` as `value is true`

A callback function of type with parameters, the that has been checked, the of this check, and of generic type variable with optional properties from the provided , to handle them before the return. By default, it uses function.

An optional of the generic type variable is assigned to the of the given function.

The return type is a as the result of its statement indicating the is true.

The return value is a indicating whether the provided is a type or an instance of that is equal to true.

boolean
value
boolean
boolean
Boolean
value
any
boolean
Boolean
isBoolean()
object
any
callback
payload
isTrue()
ResultCallback
resultCallback()
value
Payload
payload
object
Payload
callback
payload
result
payload
result
payload