isDefined

分类

导出大小

103 B

上次更改

7 个月前

对 Ref 进行非空值检查的类型守卫。

用法

import { isDefined
 } from '@vueuse/core'

const example
 = ref
(Math
.random
() ? 'example' : undefined
) // Ref<string | undefined>

if (isDefined
(example
))
  example
 // Ref<string>

类型声明

export type IsDefinedReturn
 = boolean
export declare function isDefined
<T
>(
  v
: ComputedRef
<T
>,
): v
 is ComputedRef
<Exclude
<T
, null | undefined>>
export declare function isDefined
<T
>(
  v
: Ref
<T
>,
): v
 is Ref
<Exclude
<T
, null | undefined>>
export declare function isDefined
<T
>(v
: T
): v
 is Exclude
<T
, null | undefined>