Function default

  • default<T>(value, predicate): asserts value is T

  • Test if the value matches the predicate. Throws an ArgumentError if the test fails.

    Type Parameters

    • T

    Parameters

    • value: unknown

      Value to test.

    • predicate: BasePredicate<T>

      Predicate to test against.

    Returns asserts value is T

  • default<T>(value, label, predicate): asserts value is T

  • Test if value matches the provided predicate. Throws an ArgumentError with the specified label if the test fails.

    Type Parameters

    • T

    Parameters

    • value: unknown

      Value to test.

    • label: string

      Label which should be used in error messages.

    • predicate: BasePredicate<T>

      Predicate to test against.

    Returns asserts value is T

Properties

any array arrayBuffer bigint boolean create dataView date error float32Array float64Array function int16Array int32Array int8Array isValid iterable map nan null nullOrUndefined number object optional promise regExp set sharedArrayBuffer string symbol typedArray uint16Array uint32Array uint8Array uint8ClampedArray undefined weakMap weakSet

Properties

any

any: (<T>(...predicates) => AnyPredicate<{
    [K in string | number | symbol]: T[K<K>] extends BasePredicate<U>
        ? U
        : never
}[number]>)

Test that the value matches at least one of the given predicates.

Type declaration

    • <T>(...predicates): AnyPredicate<{
          [K in string | number | symbol]: T[K<K>] extends BasePredicate<U>
              ? U
              : never
      }[number]>

    • Type Parameters

      • T extends readonly BasePredicate[]

      Parameters

      • Rest ...predicates: T

      Returns AnyPredicate<{
          [K in string | number | symbol]: T[K<K>] extends BasePredicate<U>
              ? U
              : never
      }[number]>

Readonly array

array: ArrayPredicate<unknown>

Test the value to be an array.

Readonly arrayBuffer

arrayBuffer: ArrayBufferPredicate<ArrayBuffer>

Test the value to be a ArrayBuffer.

Readonly bigint

bigint: BigIntPredicate

Test the value to be an bigint.

Readonly boolean

boolean: BooleanPredicate

Test the value to be a boolean.

create

create: (<T>(predicate) => ReusableValidator<T>) & (<T>(label, predicate) => ReusableValidator<T>)

Create a reusable validator.

Type declaration

Type declaration

Param: predicate

Predicate used in the validator function.

Readonly dataView

dataView: DataViewPredicate

Test the value to be a DataView.

Readonly date

date: DatePredicate

Test the value to be a Date.

Readonly error

error: ErrorPredicate

Test the value to be an Error.

Readonly float32Array

float32Array: TypedArrayPredicate<Float32Array>

Test the value to be a Float32Array.

Readonly float64Array

float64Array: TypedArrayPredicate<Float64Array>

Test the value to be a Float64Array.

Readonly function

function: Predicate<Function>

Test the value to be a Function.

Readonly int16Array

int16Array: TypedArrayPredicate<Int16Array>

Test the value to be a Int16Array.

Readonly int32Array

int32Array: TypedArrayPredicate<Int32Array>

Test the value to be a Int32Array.

Readonly int8Array

int8Array: TypedArrayPredicate<Int8Array>

Test the value to be a Int8Array.

isValid

isValid: (<T>(value, predicate) => value is T)

Returns true if the value matches the predicate, otherwise returns false.

Type declaration

    • <T>(value, predicate): value is T

    • Type Parameters

      • T

      Parameters

      • value: unknown

        Value to test.

      • predicate: BasePredicate<T>

        Predicate to test against.

      Returns value is T

Readonly iterable

iterable: Predicate<Iterable<unknown>>

Test the value to be Iterable.

Readonly map

map: MapPredicate<unknown, unknown>

Test the value to be a Map.

Readonly nan

nan: Predicate<number>

Test the value to be not a number.

Readonly null

null: Predicate<null>

Test the value to be null.

Readonly nullOrUndefined

nullOrUndefined: Predicate<undefined | null>

Test the value to be null or undefined.

Readonly number

number: NumberPredicate

Test the value to be a number.

Readonly object

object: ObjectPredicate<object>

Test the value to be an object.

Readonly optional

optional: {
    any: (<T>(...predicates) => AnyPredicate<{
        [K in string | number | symbol]: T[K<K>] extends BasePredicate<U>
            ? U
            : never
    }[number]>);
    array: ArrayPredicate<unknown> & BasePredicate<undefined | unknown[]>;
    arrayBuffer: ArrayBufferPredicate<ArrayBuffer> & BasePredicate<undefined | ArrayBuffer>;
    bigint: BigIntPredicate & BasePredicate<undefined | bigint>;
    boolean: BooleanPredicate & BasePredicate<undefined | boolean>;
    dataView: DataViewPredicate & BasePredicate<undefined | DataView>;
    date: DatePredicate & BasePredicate<undefined | Date>;
    error: ErrorPredicate & BasePredicate<undefined | Error>;
    float32Array: TypedArrayPredicate<Float32Array> & BasePredicate<undefined | Float32Array>;
    float64Array: TypedArrayPredicate<Float64Array> & BasePredicate<undefined | Float64Array>;
    function: Predicate<Function> & BasePredicate<undefined | Function>;
    int16Array: TypedArrayPredicate<Int16Array> & BasePredicate<undefined | Int16Array>;
    int32Array: TypedArrayPredicate<Int32Array> & BasePredicate<undefined | Int32Array>;
    int8Array: TypedArrayPredicate<Int8Array> & BasePredicate<undefined | Int8Array>;
    iterable: Predicate<Iterable<unknown>> & BasePredicate<undefined | Iterable<unknown>>;
    map: MapPredicate<unknown, unknown> & BasePredicate<undefined | Map<unknown, unknown>>;
    nan: Predicate<number> & BasePredicate<undefined | number>;
    null: Predicate<null> & BasePredicate<undefined | null>;
    nullOrUndefined: Predicate<undefined | null> & BasePredicate<undefined | null>;
    number: NumberPredicate & BasePredicate<undefined | number>;
    object: ObjectPredicate<object> & BasePredicate<undefined | object>;
    promise: Predicate<Promise<unknown>> & BasePredicate<undefined | Promise<unknown>>;
    regExp: Predicate<RegExp> & BasePredicate<undefined | RegExp>;
    set: SetPredicate<unknown> & BasePredicate<undefined | Set<unknown>>;
    sharedArrayBuffer: ArrayBufferPredicate<SharedArrayBuffer> & BasePredicate<undefined | SharedArrayBuffer>;
    string: StringPredicate & BasePredicate<undefined | string>;
    symbol: Predicate<symbol> & BasePredicate<undefined | symbol>;
    typedArray: TypedArrayPredicate<TypedArray> & BasePredicate<undefined | TypedArray>;
    uint16Array: TypedArrayPredicate<Uint16Array> & BasePredicate<undefined | Uint16Array>;
    uint32Array: TypedArrayPredicate<Uint32Array> & BasePredicate<undefined | Uint32Array>;
    uint8Array: TypedArrayPredicate<Uint8Array> & BasePredicate<undefined | Uint8Array>;
    uint8ClampedArray: TypedArrayPredicate<Uint8ClampedArray> & BasePredicate<undefined | Uint8ClampedArray>;
    undefined: Predicate<undefined> & BasePredicate<undefined>;
    weakMap: WeakMapPredicate<object> & BasePredicate<undefined | WeakMap<object, unknown>>;
    weakSet: WeakSetPredicate<object> & BasePredicate<undefined | WeakSet<object>>;
}

Make the following predicate optional so it doesn't fail when the value is undefined.

Type declaration

  • any: (<T>(...predicates) => AnyPredicate<{
        [K in string | number | symbol]: T[K<K>] extends BasePredicate<U>
            ? U
            : never
    }[number]>)

    Test that the value matches at least one of the given predicates.

      • <T>(...predicates): AnyPredicate<{
            [K in string | number | symbol]: T[K<K>] extends BasePredicate<U>
                ? U
                : never
        }[number]>

      • Type Parameters

        • T extends readonly BasePredicate[]

        Parameters

        • Rest ...predicates: T

        Returns AnyPredicate<{
            [K in string | number | symbol]: T[K<K>] extends BasePredicate<U>
                ? U
                : never
        }[number]>

  • Readonly array: ArrayPredicate<unknown> & BasePredicate<undefined | unknown[]>

    Test the value to be an array.

  • Readonly arrayBuffer: ArrayBufferPredicate<ArrayBuffer> & BasePredicate<undefined | ArrayBuffer>

    Test the value to be a ArrayBuffer.

  • Readonly bigint: BigIntPredicate & BasePredicate<undefined | bigint>

    Test the value to be an bigint.

  • Readonly boolean: BooleanPredicate & BasePredicate<undefined | boolean>

    Test the value to be a boolean.

  • Readonly dataView: DataViewPredicate & BasePredicate<undefined | DataView>

    Test the value to be a DataView.

  • Readonly date: DatePredicate & BasePredicate<undefined | Date>

    Test the value to be a Date.

  • Readonly error: ErrorPredicate & BasePredicate<undefined | Error>

    Test the value to be an Error.

  • Readonly float32Array: TypedArrayPredicate<Float32Array> & BasePredicate<undefined | Float32Array>

    Test the value to be a Float32Array.

  • Readonly float64Array: TypedArrayPredicate<Float64Array> & BasePredicate<undefined | Float64Array>

    Test the value to be a Float64Array.

  • Readonly function: Predicate<Function> & BasePredicate<undefined | Function>

    Test the value to be a Function.

  • Readonly int16Array: TypedArrayPredicate<Int16Array> & BasePredicate<undefined | Int16Array>

    Test the value to be a Int16Array.

  • Readonly int32Array: TypedArrayPredicate<Int32Array> & BasePredicate<undefined | Int32Array>

    Test the value to be a Int32Array.

  • Readonly int8Array: TypedArrayPredicate<Int8Array> & BasePredicate<undefined | Int8Array>

    Test the value to be a Int8Array.

  • Readonly iterable: Predicate<Iterable<unknown>> & BasePredicate<undefined | Iterable<unknown>>

    Test the value to be Iterable.

  • Readonly map: MapPredicate<unknown, unknown> & BasePredicate<undefined | Map<unknown, unknown>>

    Test the value to be a Map.

  • Readonly nan: Predicate<number> & BasePredicate<undefined | number>

    Test the value to be not a number.

  • Readonly null: Predicate<null> & BasePredicate<undefined | null>

    Test the value to be null.

  • Readonly nullOrUndefined: Predicate<undefined | null> & BasePredicate<undefined | null>

    Test the value to be null or undefined.

  • Readonly number: NumberPredicate & BasePredicate<undefined | number>

    Test the value to be a number.

  • Readonly object: ObjectPredicate<object> & BasePredicate<undefined | object>

    Test the value to be an object.

  • Readonly promise: Predicate<Promise<unknown>> & BasePredicate<undefined | Promise<unknown>>

    Test the value to be a Promise.

  • Readonly regExp: Predicate<RegExp> & BasePredicate<undefined | RegExp>

    Test the value to be a RegExp.

  • Readonly set: SetPredicate<unknown> & BasePredicate<undefined | Set<unknown>>

    Test the value to be a Set.

  • Readonly sharedArrayBuffer: ArrayBufferPredicate<SharedArrayBuffer> & BasePredicate<undefined | SharedArrayBuffer>

    Test the value to be a SharedArrayBuffer.

  • Readonly string: StringPredicate & BasePredicate<undefined | string>

    Test the value to be a string.

  • Readonly symbol: Predicate<symbol> & BasePredicate<undefined | symbol>

    Test the value to be a Symbol.

  • Readonly typedArray: TypedArrayPredicate<TypedArray> & BasePredicate<undefined | TypedArray>

    Test the value to be a typed array.

  • Readonly uint16Array: TypedArrayPredicate<Uint16Array> & BasePredicate<undefined | Uint16Array>

    Test the value to be a Uint16Array.

  • Readonly uint32Array: TypedArrayPredicate<Uint32Array> & BasePredicate<undefined | Uint32Array>

    Test the value to be a Uint32Array.

  • Readonly uint8Array: TypedArrayPredicate<Uint8Array> & BasePredicate<undefined | Uint8Array>

    Test the value to be a Uint8Array.

  • Readonly uint8ClampedArray: TypedArrayPredicate<Uint8ClampedArray> & BasePredicate<undefined | Uint8ClampedArray>

    Test the value to be a Uint8ClampedArray.

  • Readonly undefined: Predicate<undefined> & BasePredicate<undefined>

    Test the value to be undefined.

  • Readonly weakMap: WeakMapPredicate<object> & BasePredicate<undefined | WeakMap<object, unknown>>

    Test the value to be a WeakMap.

  • Readonly weakSet: WeakSetPredicate<object> & BasePredicate<undefined | WeakSet<object>>

    Test the value to be a WeakSet.

Readonly promise

promise: Predicate<Promise<unknown>>

Test the value to be a Promise.

Readonly regExp

regExp: Predicate<RegExp>

Test the value to be a RegExp.

Readonly set

set: SetPredicate<unknown>

Test the value to be a Set.

Readonly sharedArrayBuffer

sharedArrayBuffer: ArrayBufferPredicate<SharedArrayBuffer>

Test the value to be a SharedArrayBuffer.

Readonly string

string: StringPredicate

Test the value to be a string.

Readonly symbol

symbol: Predicate<symbol>

Test the value to be a Symbol.

Readonly typedArray

typedArray: TypedArrayPredicate<TypedArray>

Test the value to be a typed array.

Readonly uint16Array

uint16Array: TypedArrayPredicate<Uint16Array>

Test the value to be a Uint16Array.

Readonly uint32Array

uint32Array: TypedArrayPredicate<Uint32Array>

Test the value to be a Uint32Array.

Readonly uint8Array

uint8Array: TypedArrayPredicate<Uint8Array>

Test the value to be a Uint8Array.

Readonly uint8ClampedArray

uint8ClampedArray: TypedArrayPredicate<Uint8ClampedArray>

Test the value to be a Uint8ClampedArray.

Readonly undefined

undefined: Predicate<undefined>

Test the value to be undefined.

Readonly weakMap

weakMap: WeakMapPredicate<object>

Test the value to be a WeakMap.

Readonly weakSet

weakSet: WeakSetPredicate<object>

Test the value to be a WeakSet.

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anyarrayarrayBufferbigintbooleancreatedataViewdateerrorfloat32Arrayfloat64Arrayfunctionint16Arrayint32Arrayint8ArrayisValiditerablemapnannullnullOrUndefinednumberobjectoptionalpromiseregExpsetsharedArrayBufferstringsymboltypedArrayuint16Arrayuint32Arrayuint8Arrayuint8ClampedArrayundefinedweakMapweakSet