@xylabs/typeof/README.md

Base functionality used throughout XY Labs TypeScript/JavaScript libraries

# @xylabs/typeof

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Base functionality used throughout XY Labs TypeScript/JavaScript libraries

## Reference

**@xylabs/typeof**

***

## Type Aliases

- [FieldType](#type-aliases/FieldType)
- [ObjectTypeShape](#type-aliases/ObjectTypeShape)
- [TypeOfTypes](#type-aliases/TypeOfTypes)
- [TypedValue](#type-aliases/TypedValue)
- [TypedKey](#type-aliases/TypedKey)
- [TypedObject](#type-aliases/TypedObject)
- [TypedArray](#type-aliases/TypedArray)
- [AnyFunction](#type-aliases/AnyFunction)
- [RecordKey](#type-aliases/RecordKey)

## Functions

- [isTypedKey](#functions/isTypedKey)
- [isTypedValue](#functions/isTypedValue)
- [isTypedArray](#functions/isTypedArray)
- [isValidTypedFieldPair](#functions/isValidTypedFieldPair)
- [isTypedObject](#functions/isTypedObject)
- [ifDefined](#functions/ifDefined)
- [ifTypeOf](#functions/ifTypeOf)
- [isUndefined](#functions/isUndefined)
- [isDefined](#functions/isDefined)
- [isNull](#functions/isNull)
- [isDefinedNotNull](#functions/isDefinedNotNull)
- [isUndefinedOrNull](#functions/isUndefinedOrNull)
- [isBigInt](#functions/isBigInt)
- [isString](#functions/isString)
- [isNumber](#functions/isNumber)
- [isObject](#functions/isObject)
- [isArray](#functions/isArray)
- [isFunction](#functions/isFunction)
- [isSymbol](#functions/isSymbol)
- [isEmptyObject](#functions/isEmptyObject)
- [isEmptyString](#functions/isEmptyString)
- [isEmptyArray](#functions/isEmptyArray)
- [isPopulatedArray](#functions/isPopulatedArray)
- [isEmpty](#functions/isEmpty)
- [isFalsy](#functions/isFalsy)
- [isTruthy](#functions/isTruthy)
- [isBoolean](#functions/isBoolean)
- [isDateString](#functions/isDateString)
- [isDate](#functions/isDate)
- [isRegExp](#functions/isRegExp)
- [isError](#functions/isError)
- [isPromise](#functions/isPromise)
- [isPromiseLike](#functions/isPromiseLike)
- [isMap](#functions/isMap)
- [isArrayBufferView](#functions/isArrayBufferView)
- [isSet](#functions/isSet)
- [isWeakMap](#functions/isWeakMap)
- [isWeakSet](#functions/isWeakSet)
- [isArrayBuffer](#functions/isArrayBuffer)
- [isDataView](#functions/isDataView)
- [isBlob](#functions/isBlob)
- [isFile](#functions/isFile)
- [isType](#functions/isType)
- [typeOf](#functions/typeOf)
- [validateType](#functions/validateType)

### functions

  ### <a id="ifDefined"></a>ifDefined

[**@xylabs/typeof**](#../README)

***

```ts
function ifDefined<T>(value, func): undefined | T;
```

## Type Parameters

### T

`T`

## Parameters

### value

`T`

### func

(`value`) => `void`

## Returns

`undefined` \| `T`

  ### <a id="ifTypeOf"></a>ifTypeOf

[**@xylabs/typeof**](#../README)

***

```ts
function ifTypeOf<T, R>(
   typeName, 
   value, 
   trueFunc, 
   isFunc?): undefined | R;
```

## Type Parameters

### T

`T`

### R

`R`

## Parameters

### typeName

[`TypeOfTypes`](#../type-aliases/TypeOfTypes)

### value

`unknown`

### trueFunc

(`value`) => `R`

### isFunc?

(`value`) => `boolean`

## Returns

`undefined` \| `R`

  ### <a id="isArray"></a>isArray

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isArray(value): value is [];
```

### Parameters

### value

`unknown`

### Returns

`value is []`

## Call Signature

```ts
function isArray<T>(value): value is Extract<T, unknown[]>;
```

### Type Parameters

### T

`T` *extends* \[\]

### Parameters

### value

`T`

### Returns

`value is Extract<T, unknown[]>`

  ### <a id="isArrayBuffer"></a>isArrayBuffer

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isArrayBuffer(value): value is ArrayBuffer;
```

### Parameters

### value

`unknown`

### Returns

`value is ArrayBuffer`

## Call Signature

```ts
function isArrayBuffer<T>(value): value is Extract<T, ArrayBuffer>;
```

### Type Parameters

### T

`T` *extends* `ArrayBuffer`

### Parameters

### value

`T`

### Returns

`value is Extract<T, ArrayBuffer>`

  ### <a id="isArrayBufferView"></a>isArrayBufferView

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isArrayBufferView(value): value is ArrayBufferView<ArrayBufferLike>;
```

### Parameters

### value

`unknown`

### Returns

`value is ArrayBufferView<ArrayBufferLike>`

## Call Signature

```ts
function isArrayBufferView<T>(value): value is Extract<T, ArrayBufferView<ArrayBufferLike>>;
```

### Type Parameters

### T

`T` *extends* `ArrayBufferView`\<`ArrayBufferLike`\>

### Parameters

### value

`T`

### Returns

`value is Extract<T, ArrayBufferView<ArrayBufferLike>>`

  ### <a id="isBigInt"></a>isBigInt

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isBigInt(value): value is bigint;
```

### Parameters

### value

`unknown`

### Returns

`value is bigint`

## Call Signature

```ts
function isBigInt<T>(value): value is Extract<T, bigint>;
```

### Type Parameters

### T

`T` *extends* `bigint`

### Parameters

### value

`T`

### Returns

`value is Extract<T, bigint>`

  ### <a id="isBlob"></a>isBlob

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isBlob(value): value is Blob;
```

### Parameters

### value

`unknown`

### Returns

`value is Blob`

## Call Signature

```ts
function isBlob<T>(value): value is Extract<T, Blob>;
```

### Type Parameters

### T

`T` *extends* `Blob`

### Parameters

### value

`T`

### Returns

`value is Extract<T, Blob>`

  ### <a id="isBoolean"></a>isBoolean

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isBoolean(value): value is boolean;
```

### Parameters

### value

`unknown`

### Returns

`value is boolean`

## Call Signature

```ts
function isBoolean<T>(value): value is Extract<T, boolean>;
```

### Type Parameters

### T

`T` *extends* `boolean`

### Parameters

### value

`T`

### Returns

`value is Extract<T, boolean>`

  ### <a id="isDataView"></a>isDataView

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isDataView(value): value is DataView<ArrayBufferLike>;
```

### Parameters

### value

`unknown`

### Returns

`value is DataView<ArrayBufferLike>`

## Call Signature

```ts
function isDataView<T>(value): value is Extract<T, DataView<ArrayBufferLike>>;
```

### Type Parameters

### T

`T`

### Parameters

### value

`T`

### Returns

`value is Extract<T, DataView<ArrayBufferLike>>`

  ### <a id="isDate"></a>isDate

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isDate(value): value is Date;
```

### Parameters

### value

`unknown`

### Returns

`value is Date`

## Call Signature

```ts
function isDate<T>(value): value is Extract<T, Date>;
```

### Type Parameters

### T

`T`

### Parameters

### value

`T`

### Returns

`value is Extract<T, Date>`

  ### <a id="isDateString"></a>isDateString

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isDateString(value): value is string;
```

### Parameters

### value

`unknown`

### Returns

`value is string`

## Call Signature

```ts
function isDateString<T>(value): value is Extract<T, string>;
```

### Type Parameters

### T

`T`

### Parameters

### value

`T`

### Returns

`value is Extract<T, string>`

  ### <a id="isDefined"></a>isDefined

[**@xylabs/typeof**](#../README)

***

```ts
function isDefined<T>(value): value is Exclude<T, undefined>;
```

## Type Parameters

### T

`T`

## Parameters

### value

`T`

## Returns

`value is Exclude<T, undefined>`

  ### <a id="isDefinedNotNull"></a>isDefinedNotNull

[**@xylabs/typeof**](#../README)

***

```ts
function isDefinedNotNull<T>(value): value is Exclude<T, undefined | null>;
```

## Type Parameters

### T

`T`

## Parameters

### value

`T`

## Returns

value is Exclude\<T, undefined \| null\>

  ### <a id="isEmpty"></a>isEmpty

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isEmpty<T>(value): value is T;
```

### Type Parameters

### T

`T`

### Parameters

### value

`unknown`

### Returns

`value is T`

## Call Signature

```ts
function isEmpty<K, V, T>(value): value is Extract<T, Record<K, never>>;
```

### Type Parameters

### K

`K` *extends* [`RecordKey`](#../type-aliases/RecordKey)

### V

`V`

### T

`T` *extends* `Record`\<`K`, `V`\>

### Parameters

### value

`T`

### Returns

`value is Extract<T, Record<K, never>>`

## Call Signature

```ts
function isEmpty<T>(value): value is Extract<T, never[]>;
```

### Type Parameters

### T

`T` *extends* `unknown`[]

### Parameters

### value

`T`

### Returns

`value is Extract<T, never[]>`

  ### <a id="isEmptyArray"></a>isEmptyArray

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isEmptyArray(value): value is [];
```

### Parameters

### value

`unknown`

### Returns

`value is []`

## Call Signature

```ts
function isEmptyArray<T>(value): value is Extract<T, unknown[]>;
```

### Type Parameters

### T

`T` *extends* `unknown`[]

### Parameters

### value

`T`

### Returns

`value is Extract<T, unknown[]>`

  ### <a id="isEmptyObject"></a>isEmptyObject

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isEmptyObject(value): value is {};
```

### Parameters

### value

`unknown`

### Returns

`value is {}`

## Call Signature

```ts
function isEmptyObject<K, V, T>(value): value is Extract<T, Record<K, never>>;
```

### Type Parameters

### K

`K` *extends* [`RecordKey`](#../type-aliases/RecordKey)

### V

`V`

### T

`T` *extends* `Record`\<`K`, `V`\>

### Parameters

### value

`T`

### Returns

`value is Extract<T, Record<K, never>>`

  ### <a id="isEmptyString"></a>isEmptyString

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isEmptyString(value): value is "";
```

### Parameters

### value

`unknown`

### Returns

`value is ""`

## Call Signature

```ts
function isEmptyString<T>(value): value is Extract<T, "">;
```

### Type Parameters

### T

`T` *extends* `string`

### Parameters

### value

`T`

### Returns

`value is Extract<T, "">`

  ### <a id="isError"></a>isError

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isError(value): value is Error;
```

### Parameters

### value

`unknown`

### Returns

`value is Error`

## Call Signature

```ts
function isError<T>(value): value is Extract<T, Error>;
```

### Type Parameters

### T

`T`

### Parameters

### value

`T`

### Returns

`value is Extract<T, Error>`

  ### <a id="isFalsy"></a>isFalsy

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isFalsy<T>(value): value is Extract<T, undefined | null | false | "" | 0 | 0n>;
```

### Type Parameters

### T

`T`

### Parameters

### value

`T`

### Returns

value is Extract\<T, undefined \| null \| false \| "" \| 0 \| 0n\>

## Call Signature

```ts
function isFalsy<T>(value): value is Extract<T, false>;
```

### Type Parameters

### T

`T` *extends* `boolean`

### Parameters

### value

`T`

### Returns

`value is Extract<T, false>`

## Call Signature

```ts
function isFalsy<T>(value): value is Extract<T, 0>;
```

### Type Parameters

### T

`T` *extends* `number`

### Parameters

### value

`T`

### Returns

`value is Extract<T, 0>`

## Call Signature

```ts
function isFalsy<T>(value): value is Extract<T, 0n>;
```

### Type Parameters

### T

`T` *extends* `bigint`

### Parameters

### value

`T`

### Returns

`value is Extract<T, 0n>`

## Call Signature

```ts
function isFalsy<T>(value): value is Extract<T, null>;
```

### Type Parameters

### T

`T` *extends* `null`

### Parameters

### value

`T`

### Returns

`value is Extract<T, null>`

## Call Signature

```ts
function isFalsy<T>(value): value is Extract<T, undefined>;
```

### Type Parameters

### T

`T` *extends* `undefined`

### Parameters

### value

`T`

### Returns

`value is Extract<T, undefined>`

## Call Signature

```ts
function isFalsy<T>(value): value is Extract<T, "">;
```

### Type Parameters

### T

`T` *extends* `string`

### Parameters

### value

`T`

### Returns

`value is Extract<T, "">`

  ### <a id="isFile"></a>isFile

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isFile(value): value is File;
```

### Parameters

### value

`unknown`

### Returns

`value is File`

## Call Signature

```ts
function isFile<T>(value): value is Extract<T, File>;
```

### Type Parameters

### T

`T` *extends* `File`

### Parameters

### value

`T`

### Returns

`value is Extract<T, File>`

  ### <a id="isFunction"></a>isFunction

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isFunction(value): value is AnyFunction;
```

### Parameters

### value

`unknown`

### Returns

`value is AnyFunction`

## Call Signature

```ts
function isFunction<T>(value): value is Extract<T, AnyFunction>;
```

### Type Parameters

### T

`T` *extends* [`AnyFunction`](#../type-aliases/AnyFunction)

### Parameters

### value

`T`

### Returns

`value is Extract<T, AnyFunction>`

  ### <a id="isMap"></a>isMap

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isMap(value): value is Map<unknown, unknown>;
```

### Parameters

### value

`unknown`

### Returns

`value is Map<unknown, unknown>`

## Call Signature

```ts
function isMap<K, V, T>(value): value is Extract<T, Map<K, V>>;
```

### Type Parameters

### K

`K`

### V

`V`

### T

`T` *extends* `Map`\<`K`, `V`\>

### Parameters

### value

`T`

### Returns

`value is Extract<T, Map<K, V>>`

  ### <a id="isNull"></a>isNull

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isNull(value): value is null;
```

### Parameters

### value

`unknown`

### Returns

`value is null`

## Call Signature

```ts
function isNull<T>(value): value is Extract<T, null>;
```

### Type Parameters

### T

`T`

### Parameters

### value

`T`

### Returns

`value is Extract<T, null>`

  ### <a id="isNumber"></a>isNumber

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isNumber(value): value is number;
```

### Parameters

### value

`unknown`

### Returns

`value is number`

## Call Signature

```ts
function isNumber<T>(value): value is Extract<T, number>;
```

### Type Parameters

### T

`T` *extends* `number`

### Parameters

### value

`T`

### Returns

`value is Extract<T, number>`

  ### <a id="isObject"></a>isObject

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isObject(value): value is object;
```

### Parameters

### value

`unknown`

### Returns

`value is object`

## Call Signature

```ts
function isObject<T>(value): value is Extract<T, object>;
```

### Type Parameters

### T

`T` *extends* `object`

### Parameters

### value

`T`

### Returns

`value is Extract<T, object>`

  ### <a id="isPopulatedArray"></a>isPopulatedArray

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isPopulatedArray(value): value is [];
```

### Parameters

### value

`unknown`

### Returns

`value is []`

## Call Signature

```ts
function isPopulatedArray<T>(value): value is Extract<T, unknown[]>;
```

### Type Parameters

### T

`T` *extends* `unknown`[]

### Parameters

### value

`T`

### Returns

`value is Extract<T, unknown[]>`

  ### <a id="isPromise"></a>isPromise

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isPromise(value): value is Promise<unknown>;
```

### Parameters

### value

`unknown`

### Returns

`value is Promise<unknown>`

## Call Signature

```ts
function isPromise<T>(value): value is Extract<T, Promise<unknown>>;
```

### Type Parameters

### T

`T`

### Parameters

### value

`T`

### Returns

`value is Extract<T, Promise<unknown>>`

  ### <a id="isPromiseLike"></a>isPromiseLike

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isPromiseLike(value): value is Promise<unknown>;
```

### Parameters

### value

`unknown`

### Returns

`value is Promise<unknown>`

## Call Signature

```ts
function isPromiseLike<T>(value): value is Extract<T, Promise<unknown>>;
```

### Type Parameters

### T

`T`

### Parameters

### value

`T`

### Returns

`value is Extract<T, Promise<unknown>>`

  ### <a id="isRegExp"></a>isRegExp

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isRegExp(value): value is RegExp;
```

### Parameters

### value

`unknown`

### Returns

`value is RegExp`

## Call Signature

```ts
function isRegExp<T>(value): value is Extract<T, RegExp>;
```

### Type Parameters

### T

`T` *extends* `RegExp`

### Parameters

### value

`T`

### Returns

`value is Extract<T, RegExp>`

  ### <a id="isSet"></a>isSet

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isSet(value): value is Set<unknown>;
```

### Parameters

### value

`unknown`

### Returns

`value is Set<unknown>`

## Call Signature

```ts
function isSet<T>(value): value is Extract<T, Set<unknown>>;
```

### Type Parameters

### T

`T` *extends* `Set`\<`unknown`\>

### Parameters

### value

`unknown`

### Returns

`value is Extract<T, Set<unknown>>`

  ### <a id="isString"></a>isString

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isString(value): value is string;
```

### Parameters

### value

`unknown`

### Returns

`value is string`

## Call Signature

```ts
function isString<T>(value): value is Extract<T, string>;
```

### Type Parameters

### T

`T` *extends* `string`

### Parameters

### value

`T`

### Returns

`value is Extract<T, string>`

  ### <a id="isSymbol"></a>isSymbol

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isSymbol(value): value is symbol;
```

### Parameters

### value

`unknown`

### Returns

`value is symbol`

## Call Signature

```ts
function isSymbol<T>(value): value is Extract<T, symbol>;
```

### Type Parameters

### T

`T` *extends* `symbol`

### Parameters

### value

`T`

### Returns

`value is Extract<T, symbol>`

  ### <a id="isTruthy"></a>isTruthy

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isTruthy<T>(value): value is Exclude<T, undefined | null | false | "" | 0 | 0n>;
```

### Type Parameters

### T

`T`

### Parameters

### value

`T`

### Returns

value is Exclude\<T, undefined \| null \| false \| "" \| 0 \| 0n\>

## Call Signature

```ts
function isTruthy<T>(value): value is Extract<T, true>;
```

### Type Parameters

### T

`T` *extends* `boolean`

### Parameters

### value

`T`

### Returns

`value is Extract<T, true>`

## Call Signature

```ts
function isTruthy<T>(value): value is Extract<T, number>;
```

### Type Parameters

### T

`T` *extends* `number`

### Parameters

### value

`T`

### Returns

`value is Extract<T, number>`

## Call Signature

```ts
function isTruthy<T>(value): value is Extract<T, bigint>;
```

### Type Parameters

### T

`T` *extends* `bigint`

### Parameters

### value

`T`

### Returns

`value is Extract<T, bigint>`

## Call Signature

```ts
function isTruthy<T>(value): value is Extract<T, null>;
```

### Type Parameters

### T

`T` *extends* `null`

### Parameters

### value

`T`

### Returns

`value is Extract<T, null>`

## Call Signature

```ts
function isTruthy<T>(value): value is Extract<T, undefined>;
```

### Type Parameters

### T

`T` *extends* `undefined`

### Parameters

### value

`T`

### Returns

`value is Extract<T, undefined>`

## Call Signature

```ts
function isTruthy<T>(value): value is Extract<T, string>;
```

### Type Parameters

### T

`T` *extends* `string`

### Parameters

### value

`T`

### Returns

`value is Extract<T, string>`

  ### <a id="isType"></a>isType

[**@xylabs/typeof**](#../README)

***

```ts
function isType(value, expectedType): boolean;
```

## Parameters

### value

`unknown`

### expectedType

[`FieldType`](#../type-aliases/FieldType)

## Returns

`boolean`

  ### <a id="isTypedArray"></a>isTypedArray

[**@xylabs/typeof**](#../README)

***

```ts
function isTypedArray(value): value is TypedArray;
```

## Parameters

### value

`unknown`

## Returns

`value is TypedArray`

  ### <a id="isTypedKey"></a>isTypedKey

[**@xylabs/typeof**](#../README)

***

```ts
function isTypedKey(value): value is string | number | symbol;
```

## Parameters

### value

`unknown`

## Returns

value is string \| number \| symbol

  ### <a id="isTypedObject"></a>isTypedObject

[**@xylabs/typeof**](#../README)

***

```ts
function isTypedObject(value): value is TypedObject;
```

## Parameters

### value

`unknown`

## Returns

`value is TypedObject`

  ### <a id="isTypedValue"></a>isTypedValue

[**@xylabs/typeof**](#../README)

***

```ts
function isTypedValue(value): value is TypedValue;
```

## Parameters

### value

`unknown`

## Returns

`value is TypedValue`

  ### <a id="isUndefined"></a>isUndefined

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isUndefined(value): value is undefined;
```

### Parameters

### value

`unknown`

### Returns

`value is undefined`

## Call Signature

```ts
function isUndefined<T>(value): value is Extract<T, undefined>;
```

### Type Parameters

### T

`T`

### Parameters

### value

`T`

### Returns

`value is Extract<T, undefined>`

  ### <a id="isUndefinedOrNull"></a>isUndefinedOrNull

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isUndefinedOrNull(value): value is undefined | null;
```

### Parameters

### value

`unknown`

### Returns

value is undefined \| null

## Call Signature

```ts
function isUndefinedOrNull<T>(value): value is Extract<T, undefined | null>;
```

### Type Parameters

### T

`T`

### Parameters

### value

`T`

### Returns

value is Extract\<T, undefined \| null\>

  ### <a id="isValidTypedFieldPair"></a>isValidTypedFieldPair

[**@xylabs/typeof**](#../README)

***

```ts
function isValidTypedFieldPair(pair): pair is [key: string | number | symbol, value: TypedValue];
```

## Parameters

### pair

\[`unknown`, `unknown`\]

## Returns

pair is \[key: string \| number \| symbol, value: TypedValue\]

  ### <a id="isWeakMap"></a>isWeakMap

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isWeakMap(value): value is WeakMap<WeakKey, unknown>;
```

### Parameters

### value

`unknown`

### Returns

`value is WeakMap<WeakKey, unknown>`

## Call Signature

```ts
function isWeakMap<K, V, T>(value): value is Extract<T, WeakMap<K, V>>;
```

### Type Parameters

### K

`K` *extends* `WeakKey`

### V

`V`

### T

`T` *extends* `WeakMap`\<`K`, `V`\>

### Parameters

### value

`T`

### Returns

`value is Extract<T, WeakMap<K, V>>`

  ### <a id="isWeakSet"></a>isWeakSet

[**@xylabs/typeof**](#../README)

***

## Call Signature

```ts
function isWeakSet(value): value is WeakSet<WeakKey>;
```

### Parameters

### value

`unknown`

### Returns

`value is WeakSet<WeakKey>`

## Call Signature

```ts
function isWeakSet<K, T>(value): value is Extract<T, WeakSet<K>>;
```

### Type Parameters

### K

`K` *extends* `WeakKey`

### T

`T` *extends* `WeakSet`\<`K`\>

### Parameters

### value

`T`

### Returns

`value is Extract<T, WeakSet<K>>`

  ### <a id="typeOf"></a>typeOf

[**@xylabs/typeof**](#../README)

***

```ts
function typeOf<T>(item): TypeOfTypes;
```

## Type Parameters

### T

`T`

## Parameters

### item

`T`

## Returns

[`TypeOfTypes`](#../type-aliases/TypeOfTypes)

  ### <a id="validateType"></a>validateType

[**@xylabs/typeof**](#../README)

***

```ts
function validateType<T>(
   typeName, 
   value, 
   optional): [undefined | T, Error[]];
```

## Type Parameters

### T

`T`

## Parameters

### typeName

[`TypeOfTypes`](#../type-aliases/TypeOfTypes)

### value

`T`

### optional

`boolean` = `false`

## Returns

\[`undefined` \| `T`, `Error`[]\]

### type-aliases

  ### <a id="AnyFunction"></a>AnyFunction

[**@xylabs/typeof**](#../README)

***

```ts
type AnyFunction = (...args) => unknown;
```

## Parameters

### args

...`unknown`[]

## Returns

`unknown`

  ### <a id="FieldType"></a>FieldType

[**@xylabs/typeof**](#../README)

***

```ts
type FieldType = 
  | "string"
  | "number"
  | "object"
  | "symbol"
  | "undefined"
  | "null"
  | "array"
  | "function";
```

  ### <a id="ObjectTypeShape"></a>ObjectTypeShape

[**@xylabs/typeof**](#../README)

***

```ts
type ObjectTypeShape = Record<string | number | symbol, FieldType>;
```

  ### <a id="RecordKey"></a>RecordKey

[**@xylabs/typeof**](#../README)

***

```ts
type RecordKey = string | number | symbol;
```

  ### <a id="TypeOfTypes"></a>TypeOfTypes

[**@xylabs/typeof**](#../README)

***

```ts
type TypeOfTypes = 
  | "string"
  | "number"
  | "object"
  | "array"
  | "buffer"
  | "null"
  | "undefined"
  | "bigint"
  | "boolean"
  | "function"
  | "symbol";
```

  ### <a id="TypedArray"></a>TypedArray

[**@xylabs/typeof**](#../README)

***

```ts
type TypedArray = TypedValue[];
```

  ### <a id="TypedKey"></a>TypedKey

[**@xylabs/typeof**](#../README)

***

```ts
type TypedKey<T> = T extends string ? T : string | number | symbol;
```

## Type Parameters

### T

`T` *extends* `string` \| `void` = `void`

  ### <a id="TypedObject"></a>TypedObject

[**@xylabs/typeof**](#../README)

***

```ts
type TypedObject = 
  | {
[key: string | number | symbol]: TypedValue;
}
  | object;
```

  ### <a id="TypedValue"></a>TypedValue

[**@xylabs/typeof**](#../README)

***

```ts
type TypedValue = 
  | bigint
  | string
  | number
  | boolean
  | null
  | TypedObject
  | TypedArray
  | Function
  | symbol
  | undefined;
```


Part of [sdk-js](https://www.npmjs.com/package/@xyo-network/sdk-js)

## Maintainers

-   [Arie Trouw](https://github.com/arietrouw) ([arietrouw.com](https://arietrouw.com))
-   [Matt Jones](https://github.com/jonesmac)
-   [Joel Carter](https://github.com/JoelBCarter)
-   [Jordan Trouw](https://github.com/jordantrouw)

## License

> See the [LICENSE](LICENSE) file for license details

## Credits

[Made with 🔥 and ❄️ by XYLabs](https://xylabs.com)

[logo]: https://cdn.xy.company/img/brand/XYPersistentCompany_Logo_Icon_Colored.svg

[main-build]: https://github.com/xylabs/sdk-js/actions/workflows/build.yml/badge.svg
[main-build-link]: https://github.com/xylabs/sdk-js/actions/workflows/build.yml
[npm-badge]: https://img.shields.io/npm/v/@xylabs/typeof.svg
[npm-link]: https://www.npmjs.com/package/@xylabs/typeof
[codacy-badge]: https://app.codacy.com/project/badge/Grade/c8e15e14f37741c18cfb47ac7245c698
[codacy-link]: https://www.codacy.com/gh/xylabs/sdk-js/dashboard?utm_source=github.com&utm_medium=referral&utm_content=xylabs/sdk-js&utm_campaign=Badge_Grade
[codeclimate-badge]: https://api.codeclimate.com/v1/badges/c5eb068f806f0b047ea7/maintainability
[codeclimate-link]: https://codeclimate.com/github/xylabs/sdk-js/maintainability
[snyk-badge]: https://snyk.io/test/github/xylabs/sdk-js/badge.svg?targetFile=package.json
[snyk-link]: https://snyk.io/test/github/xylabs/sdk-js?targetFile=package.json

[npm-downloads-badge]: https://img.shields.io/npm/dw/@xylabs/typeof
[npm-license-badge]: https://img.shields.io/npm/l/@xylabs/typeof

[jsdelivr-badge]: https://data.jsdelivr.com/v1/package/npm/@xylabs/typeof/badge
[jsdelivr-link]: https://www.jsdelivr.com/package/npm/@xylabs/typeof

[socket-badge]: https://socket.dev/api/badge/npm/package/@xylabs/typeof
[socket-link]: https://socket.dev/npm/package/@xylabs/typeof