Function assertType

assertType<T>(subject: T): asserts subject is T
💥 immediate 🚦 assertion

Assert the subject satisfies the specified type T
Type Parameters
- T
Parameters
- subject: T
Returns asserts subject is T
- Defined in packages/type-plus/src/assertion/assert_type.ts:12
assertType<T>(
subject: unknown,
validator: (s: T) => boolean,
): asserts subject is T
💥 immediate 🚦 assertion

Assert the subject satisfies the specified type T
Type Parameters
- T
Parameters
- subject: unknown
- validator: (s: T) => boolean
Returns asserts subject is T
- Defined in packages/type-plus/src/assertion/assert_type.ts:13
assertType<T extends new (..._args: any[]) => any>(
subject: unknown,
classConstructor: T,
): asserts subject is InstanceType<T>
Type Parameters
- T extends new (..._args: any[]) => any
Parameters
- subject: unknown
- classConstructor: T
Returns asserts subject is InstanceType<T>
Deprecated
this is not a failsafe test
- Defined in packages/type-plus/src/assertion/assert_type.ts:17

Methods

as

as<T>(_subject: unknown): asserts _subject is T
Type Parameters
- T
Parameters
- _subject: unknown
Returns asserts _subject is T
- Defined in packages/type-plus/src/assertion/assert_type.ts:119

custom

custom<T>(
validator: (s: T) => boolean,
): (subject: unknown) => asserts subject is T
creates a custom assertion function with standard TypeError. Currently this requires explicity type annotation, thus making it hard to use: https://github.com/microsoft/TypeScript/issues/41047
Type Parameters
- T
Parameters
- validator: (s: T) => boolean
Returns (subject: unknown) => asserts subject is T
- Defined in packages/type-plus/src/assertion/assert_type.ts:112

isBoolean

isBoolean(subject: boolean): asserts subject is boolean
Parameters
- subject: boolean
Returns asserts subject is boolean
- Defined in packages/type-plus/src/assertion/assert_type.ts:50

isConstructor

isConstructor(subject: AnyConstructor): asserts subject is AnyConstructor
💀 deprecated. It does not work in all cases.

It passes for function that can be called with new. If the subject is an arrow function, it can still return true after compilation.
Parameters
- subject: AnyConstructor
Returns asserts subject is AnyConstructor
- Defined in packages/type-plus/src/assertion/assert_type.ts:93

isError

isError(subject: Error): asserts subject is Error
Parameters
- subject: Error
Returns asserts subject is Error
- Defined in packages/type-plus/src/assertion/assert_type.ts:97

isFalse

isFalse(subject: false): asserts subject is false
Parameters
- subject: false
Returns asserts subject is false
- Defined in packages/type-plus/src/assertion/assert_type.ts:65

isFunction

isFunction(subject: AnyFunction): asserts subject is AnyFunction
Parameters
- subject: AnyFunction
Returns asserts subject is AnyFunction
- Defined in packages/type-plus/src/assertion/assert_type.ts:80

isNever

isNever(_subject: never): asserts _subject is never
Parameters
- _subject: never
Returns asserts _subject is never
- Defined in packages/type-plus/src/assertion/assert_type.ts:104

isNull

isNull(subject: null): asserts subject is null
Parameters
- subject: null
Returns asserts subject is null
- Defined in packages/type-plus/src/assertion/assert_type.ts:36

isNumber

isNumber(subject: number): asserts subject is number
Parameters
- subject: number
Returns asserts subject is number
- Defined in packages/type-plus/src/assertion/assert_type.ts:43

isString

isString(subject: string): asserts subject is string
Parameters
- subject: string
Returns asserts subject is string
- Defined in packages/type-plus/src/assertion/assert_type.ts:73

isTrue

isTrue(subject: true): asserts subject is true
Parameters
- subject: true
Returns asserts subject is true
- Defined in packages/type-plus/src/assertion/assert_type.ts:57

isUndefined

isUndefined(subject: undefined): asserts subject is undefined
Parameters
- subject: undefined
Returns asserts subject is undefined
- Defined in packages/type-plus/src/assertion/assert_type.ts:29

noBoolean

noBoolean<S>(subject: Exclude<S, boolean>): void
Type Parameters
- S
Parameters
- subject: Exclude<S, boolean>
Returns void
- Defined in packages/type-plus/src/assertion/assert_type.ts:53

noError

noError<S>(subject: Exclude<S, Error>): void
Type Parameters
- S
Parameters
- subject: Exclude<S, Error>
Returns void
- Defined in packages/type-plus/src/assertion/assert_type.ts:100

noFalse

noFalse<S>(subject: Exclude<S, false>): void
Type Parameters
- S
Parameters
- subject: Exclude<S, false>
Returns void
- Defined in packages/type-plus/src/assertion/assert_type.ts:68

noFunction

noFunction<S>(subject: Exclude<S, AnyFunction>): void
Type Parameters
- S
Parameters
- subject: Exclude<S, AnyFunction>
Returns void
- Defined in packages/type-plus/src/assertion/assert_type.ts:83

noNull

noNull<S>(subject: Exclude<S, null>): void
Type Parameters
- S
Parameters
- subject: Exclude<S, null>
Returns void
- Defined in packages/type-plus/src/assertion/assert_type.ts:39

noNumber

noNumber<S>(subject: Exclude<S, number>): void
Type Parameters
- S
Parameters
- subject: Exclude<S, number>
Returns void
- Defined in packages/type-plus/src/assertion/assert_type.ts:46

noString

noString<S>(subject: Exclude<S, string>): void
Type Parameters
- S
Parameters
- subject: Exclude<S, string>
Returns void
- Defined in packages/type-plus/src/assertion/assert_type.ts:76

noTrue

noTrue<S>(subject: Exclude<S, true>): void
Type Parameters
- S
Parameters
- subject: Exclude<S, true>
Returns void
- Defined in packages/type-plus/src/assertion/assert_type.ts:60

noUndefined

noUndefined<S>(subject: Exclude<S, undefined>): void
Type Parameters
- S
Parameters
- subject: Exclude<S, undefined>
Returns void
- Defined in packages/type-plus/src/assertion/assert_type.ts:32

Function assertType

Type Parameters

Parameters

Returns asserts subject is T

Type Parameters

Parameters

Returns asserts subject is T

Type Parameters

Parameters

Returns asserts subject is InstanceType<T>

Deprecated

Index

Methods

Methods

as

Type Parameters

Parameters

Returns asserts _subject is T

custom

Type Parameters

Parameters

Returns (subject: unknown) => asserts subject is T

isBoolean

Parameters

Returns asserts subject is boolean

isConstructor

Parameters

Returns asserts subject is AnyConstructor

isError

Parameters

Returns asserts subject is Error

isFalse

Parameters

Returns asserts subject is false

isFunction

Parameters

Returns asserts subject is AnyFunction

isNever

Parameters

Returns asserts _subject is never

isNull

Parameters

Returns asserts subject is null

isNumber

Parameters

Returns asserts subject is number

isString

Parameters

Returns asserts subject is string

isTrue

Parameters

Returns asserts subject is true

isUndefined

Parameters

Returns asserts subject is undefined

noBoolean

Type Parameters

Parameters

Returns void

noError

Type Parameters

Parameters

Returns void

noFalse

Type Parameters

Parameters

Returns void

noFunction

Type Parameters

Parameters

Returns void

noNull

Type Parameters

Parameters

Returns void

noNumber

Type Parameters

Parameters

Returns void

noString