/// /// /// export type Class = new (...args: any[]) => T; export const enum TypeName { null = 'null', boolean = 'boolean', undefined = 'undefined', string = 'string', number = 'number', bigint = 'bigint', symbol = 'symbol', Function = 'Function', Generator = 'Generator', AsyncGenerator = 'AsyncGenerator', GeneratorFunction = 'GeneratorFunction', AsyncGeneratorFunction = 'AsyncGeneratorFunction', AsyncFunction = 'AsyncFunction', Observable = 'Observable', Array = 'Array', Buffer = 'Buffer', Object = 'Object', RegExp = 'RegExp', Date = 'Date', Error = 'Error', Map = 'Map', Set = 'Set', WeakMap = 'WeakMap', WeakSet = 'WeakSet', Int8Array = 'Int8Array', Uint8Array = 'Uint8Array', Uint8ClampedArray = 'Uint8ClampedArray', Int16Array = 'Int16Array', Uint16Array = 'Uint16Array', Int32Array = 'Int32Array', Uint32Array = 'Uint32Array', Float32Array = 'Float32Array', Float64Array = 'Float64Array', BigInt64Array = 'BigInt64Array', BigUint64Array = 'BigUint64Array', ArrayBuffer = 'ArrayBuffer', SharedArrayBuffer = 'SharedArrayBuffer', DataView = 'DataView', Promise = 'Promise', URL = 'URL' } const {toString} = Object.prototype; const isOfType = (type: string) => (value: unknown): value is T => typeof value === type; const getObjectType = (value: unknown): TypeName | undefined => { const objectName = toString.call(value).slice(8, -1); if (objectName) { return objectName as TypeName; } return undefined; }; const isObjectOfType = (type: TypeName) => (value: unknown): value is T => getObjectType(value) === type; function is(value: unknown): TypeName { switch (value) { case null: return TypeName.null; case true: case false: return TypeName.boolean; default: } switch (typeof value) { case 'undefined': return TypeName.undefined; case 'string': return TypeName.string; case 'number': return TypeName.number; case 'bigint': return TypeName.bigint; case 'symbol': return TypeName.symbol; default: } if (is.function_(value)) { return TypeName.Function; } if (is.observable(value)) { return TypeName.Observable; } if (is.array(value)) { return TypeName.Array; } if (is.buffer(value)) { return TypeName.Buffer; } const tagType = getObjectType(value); if (tagType) { return tagType; } if (value instanceof String || value instanceof Boolean || value instanceof Number) { throw new TypeError('Please don\'t use object wrappers for primitive types'); } return TypeName.Object; } is.undefined = isOfType('undefined'); is.string = isOfType('string'); const isNumberType = isOfType('number'); is.number = (value: unknown): value is number => isNumberType(value) && !is.nan(value); is.bigint = isOfType('bigint'); // eslint-disable-next-line @typescript-eslint/ban-types is.function_ = isOfType('function'); is.null_ = (value: unknown): value is null => value === null; is.class_ = (value: unknown): value is Class => is.function_(value) && value.toString().startsWith('class '); is.boolean = (value: unknown): value is boolean => value === true || value === false; is.symbol = isOfType('symbol'); is.numericString = (value: unknown): value is string => is.string(value) && value.length > 0 && !Number.isNaN(Number(value)); is.array = Array.isArray; is.buffer = (value: unknown): value is Buffer => (value as any)?.constructor?.isBuffer?.(value) ?? false; is.nullOrUndefined = (value: unknown): value is null | undefined => is.null_(value) || is.undefined(value); is.object = (value: unknown): value is object => !is.null_(value) && (typeof value === 'object' || is.function_(value)); is.iterable = (value: unknown): value is IterableIterator => is.function_((value as IterableIterator)?.[Symbol.iterator]); is.asyncIterable = (value: unknown): value is AsyncIterableIterator => is.function_((value as AsyncIterableIterator)?.[Symbol.asyncIterator]); is.generator = (value: unknown): value is Generator => is.iterable(value) && is.function_(value.next) && is.function_(value.throw); is.asyncGenerator = (value: unknown): value is AsyncGenerator => is.asyncIterable(value) && is.function_(value.next) && is.function_(value.throw); is.nativePromise = (value: unknown): value is Promise => isObjectOfType>(TypeName.Promise)(value); const hasPromiseAPI = (value: unknown): value is Promise => is.function_((value as Promise)?.then) && is.function_((value as Promise)?.catch); is.promise = (value: unknown): value is Promise => is.nativePromise(value) || hasPromiseAPI(value); is.generatorFunction = isObjectOfType(TypeName.GeneratorFunction); is.asyncGeneratorFunction = (value: unknown): value is ((...args: any[]) => Promise) => getObjectType(value) === TypeName.AsyncGeneratorFunction; is.asyncFunction = (value: unknown): value is ((...args: any[]) => Promise) => getObjectType(value) === TypeName.AsyncFunction; // eslint-disable-next-line no-prototype-builtins, @typescript-eslint/ban-types is.boundFunction = (value: unknown): value is Function => is.function_(value) && !value.hasOwnProperty('prototype'); is.regExp = isObjectOfType(TypeName.RegExp); is.date = isObjectOfType(TypeName.Date); is.error = isObjectOfType(TypeName.Error); is.map = (value: unknown): value is Map => isObjectOfType>(TypeName.Map)(value); is.set = (value: unknown): value is Set => isObjectOfType>(TypeName.Set)(value); is.weakMap = (value: unknown): value is WeakMap => isObjectOfType>(TypeName.WeakMap)(value); is.weakSet = (value: unknown): value is WeakSet => isObjectOfType>(TypeName.WeakSet)(value); is.int8Array = isObjectOfType(TypeName.Int8Array); is.uint8Array = isObjectOfType(TypeName.Uint8Array); is.uint8ClampedArray = isObjectOfType(TypeName.Uint8ClampedArray); is.int16Array = isObjectOfType(TypeName.Int16Array); is.uint16Array = isObjectOfType(TypeName.Uint16Array); is.int32Array = isObjectOfType(TypeName.Int32Array); is.uint32Array = isObjectOfType(TypeName.Uint32Array); is.float32Array = isObjectOfType(TypeName.Float32Array); is.float64Array = isObjectOfType(TypeName.Float64Array); is.bigInt64Array = isObjectOfType(TypeName.BigInt64Array); is.bigUint64Array = isObjectOfType(TypeName.BigUint64Array); is.arrayBuffer = isObjectOfType(TypeName.ArrayBuffer); is.sharedArrayBuffer = isObjectOfType(TypeName.SharedArrayBuffer); is.dataView = isObjectOfType(TypeName.DataView); is.directInstanceOf = (instance: unknown, class_: Class): instance is T => Object.getPrototypeOf(instance) === class_.prototype; is.urlInstance = (value: unknown): value is URL => isObjectOfType(TypeName.URL)(value); is.urlString = (value: unknown): value is string => { if (!is.string(value)) { return false; } try { new URL(value); // eslint-disable-line no-new return true; } catch { return false; } }; // TODO: Use the `not` operator with a type guard here when it's available. // Example: `is.truthy = (value: unknown): value is (not false | not 0 | not '' | not undefined | not null) => Boolean(value);` is.truthy = (value: unknown) => Boolean(value); // Example: `is.falsy = (value: unknown): value is (not true | 0 | '' | undefined | null) => Boolean(value);` is.falsy = (value: unknown) => !value; is.nan = (value: unknown) => Number.isNaN(value as number); const primitiveTypeOfTypes = new Set([ 'undefined', 'string', 'number', 'bigint', 'boolean', 'symbol' ]); // TODO: This should be able to be `not object` when the `not` operator is out export type Primitive = | null | undefined | string | number | bigint | boolean | symbol; is.primitive = (value: unknown): value is Primitive => is.null_(value) || primitiveTypeOfTypes.has(typeof value); is.integer = (value: unknown): value is number => Number.isInteger(value as number); is.safeInteger = (value: unknown): value is number => Number.isSafeInteger(value as number); is.plainObject = (value: unknown): value is Record => { // From: https://github.com/sindresorhus/is-plain-obj/blob/master/index.js if (getObjectType(value) !== TypeName.Object) { return false; } const prototype = Object.getPrototypeOf(value); return prototype === null || prototype === Object.getPrototypeOf({}); }; const typedArrayTypes = new Set([ TypeName.Int8Array, TypeName.Uint8Array, TypeName.Uint8ClampedArray, TypeName.Int16Array, TypeName.Uint16Array, TypeName.Int32Array, TypeName.Uint32Array, TypeName.Float32Array, TypeName.Float64Array, TypeName.BigInt64Array, TypeName.BigUint64Array ]); export type TypedArray = | Int8Array | Uint8Array | Uint8ClampedArray | Int16Array | Uint16Array | Int32Array | Uint32Array | Float32Array | Float64Array | BigInt64Array | BigUint64Array; is.typedArray = (value: unknown): value is TypedArray => { const objectType = getObjectType(value); if (objectType === undefined) { return false; } return typedArrayTypes.has(objectType); }; export interface ArrayLike { readonly [index: number]: T; readonly length: number; } const isValidLength = (value: unknown): value is number => is.safeInteger(value) && value >= 0; is.arrayLike = (value: unknown): value is ArrayLike => !is.nullOrUndefined(value) && !is.function_(value) && isValidLength((value as ArrayLike).length); is.inRange = (value: number, range: number | number[]): value is number => { if (is.number(range)) { return value >= Math.min(0, range) && value <= Math.max(range, 0); } if (is.array(range) && range.length === 2) { return value >= Math.min(...range) && value <= Math.max(...range); } throw new TypeError(`Invalid range: ${JSON.stringify(range)}`); }; const NODE_TYPE_ELEMENT = 1; const DOM_PROPERTIES_TO_CHECK = [ 'innerHTML', 'ownerDocument', 'style', 'attributes', 'nodeValue' ]; is.domElement = (value: unknown): value is Element => is.object(value) && (value as Element).nodeType === NODE_TYPE_ELEMENT && is.string((value as Element).nodeName) && !is.plainObject(value) && DOM_PROPERTIES_TO_CHECK.every(property => property in (value as Element)); export interface ObservableLike { subscribe(observer: (value: unknown) => void): void; [Symbol.observable](): ObservableLike; } is.observable = (value: unknown): value is ObservableLike => { if (!value) { return false; } // eslint-disable-next-line no-use-extend-native/no-use-extend-native if (value === (value as any)[Symbol.observable]?.()) { return true; } if (value === (value as any)['@@observable']?.()) { return true; } return false; }; export interface NodeStream extends NodeJS.EventEmitter { pipe(destination: T, options?: {end?: boolean}): T; } is.nodeStream = (value: unknown): value is NodeStream => is.object(value) && is.function_((value as NodeStream).pipe) && !is.observable(value); is.infinite = (value: unknown): value is number => value === Infinity || value === -Infinity; const isAbsoluteMod2 = (remainder: number) => (value: number): value is number => is.integer(value) && Math.abs(value % 2) === remainder; is.evenInteger = isAbsoluteMod2(0); is.oddInteger = isAbsoluteMod2(1); is.emptyArray = (value: unknown): value is never[] => is.array(value) && value.length === 0; is.nonEmptyArray = (value: unknown): value is unknown[] => is.array(value) && value.length > 0; is.emptyString = (value: unknown): value is '' => is.string(value) && value.length === 0; // TODO: Use `not ''` when the `not` operator is available. is.nonEmptyString = (value: unknown): value is string => is.string(value) && value.length > 0; const isWhiteSpaceString = (value: unknown): value is string => is.string(value) && !/\S/.test(value); is.emptyStringOrWhitespace = (value: unknown): value is string => is.emptyString(value) || isWhiteSpaceString(value); is.emptyObject = (value: unknown): value is Record => is.object(value) && !is.map(value) && !is.set(value) && Object.keys(value).length === 0; // TODO: Use `not` operator here to remove `Map` and `Set` from type guard: // - https://github.com/Microsoft/TypeScript/pull/29317 is.nonEmptyObject = (value: unknown): value is Record => is.object(value) && !is.map(value) && !is.set(value) && Object.keys(value).length > 0; is.emptySet = (value: unknown): value is Set => is.set(value) && value.size === 0; is.nonEmptySet = (value: unknown): value is Set => is.set(value) && value.size > 0; is.emptyMap = (value: unknown): value is Map => is.map(value) && value.size === 0; is.nonEmptyMap = (value: unknown): value is Map => is.map(value) && value.size > 0; export type Predicate = (value: unknown) => boolean; type ArrayMethod = (fn: (value: unknown, index: number, array: unknown[]) => boolean, thisArg?: unknown) => boolean; const predicateOnArray = (method: ArrayMethod, predicate: Predicate, values: unknown[]) => { if (!is.function_(predicate)) { throw new TypeError(`Invalid predicate: ${JSON.stringify(predicate)}`); } if (values.length === 0) { throw new TypeError('Invalid number of values'); } return method.call(values, predicate); }; is.any = (predicate: Predicate | Predicate[], ...values: unknown[]): boolean => { const predicates = is.array(predicate) ? predicate : [predicate]; return predicates.some(singlePredicate => predicateOnArray(Array.prototype.some, singlePredicate, values) ); }; is.all = (predicate: Predicate, ...values: unknown[]): boolean => predicateOnArray(Array.prototype.every, predicate, values); const assertType = (condition: boolean, description: string, value: unknown): asserts condition => { if (!condition) { throw new TypeError(`Expected value which is \`${description}\`, received value of type \`${is(value)}\`.`); } }; export const enum AssertionTypeDescription { class_ = 'Class', numericString = 'string with a number', nullOrUndefined = 'null or undefined', iterable = 'Iterable', asyncIterable = 'AsyncIterable', nativePromise = 'native Promise', urlString = 'string with a URL', truthy = 'truthy', falsy = 'falsy', nan = 'NaN', primitive = 'primitive', integer = 'integer', safeInteger = 'integer', plainObject = 'plain object', arrayLike = 'array-like', typedArray = 'TypedArray', domElement = 'Element', nodeStream = 'Node.js Stream', infinite = 'infinite number', emptyArray = 'empty array', nonEmptyArray = 'non-empty array', emptyString = 'empty string', nonEmptyString = 'non-empty string', emptyStringOrWhitespace = 'empty string or whitespace', emptyObject = 'empty object', nonEmptyObject = 'non-empty object', emptySet = 'empty set', nonEmptySet = 'non-empty set', emptyMap = 'empty map', nonEmptyMap = 'non-empty map', evenInteger = 'even integer', oddInteger = 'odd integer', directInstanceOf = 'T', inRange = 'in range', any = 'predicate returns truthy for any value', all = 'predicate returns truthy for all values', } // Type assertions have to be declared with an explicit type. interface Assert { // Unknowns. undefined: (value: unknown) => asserts value is undefined; string: (value: unknown) => asserts value is string; number: (value: unknown) => asserts value is number; bigint: (value: unknown) => asserts value is bigint; // eslint-disable-next-line @typescript-eslint/ban-types function_: (value: unknown) => asserts value is Function; null_: (value: unknown) => asserts value is null; class_: (value: unknown) => asserts value is Class; boolean: (value: unknown) => asserts value is boolean; symbol: (value: unknown) => asserts value is symbol; numericString: (value: unknown) => asserts value is string; array: (value: unknown) => asserts value is T[]; buffer: (value: unknown) => asserts value is Buffer; nullOrUndefined: (value: unknown) => asserts value is null | undefined; object: (value: unknown) => asserts value is Record; iterable: (value: unknown) => asserts value is Iterable; asyncIterable: (value: unknown) => asserts value is AsyncIterable; generator: (value: unknown) => asserts value is Generator; asyncGenerator: (value: unknown) => asserts value is AsyncGenerator; nativePromise: (value: unknown) => asserts value is Promise; promise: (value: unknown) => asserts value is Promise; generatorFunction: (value: unknown) => asserts value is GeneratorFunction; asyncGeneratorFunction: (value: unknown) => asserts value is AsyncGeneratorFunction; // eslint-disable-next-line @typescript-eslint/ban-types asyncFunction: (value: unknown) => asserts value is Function; // eslint-disable-next-line @typescript-eslint/ban-types boundFunction: (value: unknown) => asserts value is Function; regExp: (value: unknown) => asserts value is RegExp; date: (value: unknown) => asserts value is Date; error: (value: unknown) => asserts value is Error; map: (value: unknown) => asserts value is Map; set: (value: unknown) => asserts value is Set; weakMap: (value: unknown) => asserts value is WeakMap; weakSet: (value: unknown) => asserts value is WeakSet; int8Array: (value: unknown) => asserts value is Int8Array; uint8Array: (value: unknown) => asserts value is Uint8Array; uint8ClampedArray: (value: unknown) => asserts value is Uint8ClampedArray; int16Array: (value: unknown) => asserts value is Int16Array; uint16Array: (value: unknown) => asserts value is Uint16Array; int32Array: (value: unknown) => asserts value is Int32Array; uint32Array: (value: unknown) => asserts value is Uint32Array; float32Array: (value: unknown) => asserts value is Float32Array; float64Array: (value: unknown) => asserts value is Float64Array; bigInt64Array: (value: unknown) => asserts value is BigInt64Array; bigUint64Array: (value: unknown) => asserts value is BigUint64Array; arrayBuffer: (value: unknown) => asserts value is ArrayBuffer; sharedArrayBuffer: (value: unknown) => asserts value is SharedArrayBuffer; dataView: (value: unknown) => asserts value is DataView; urlInstance: (value: unknown) => asserts value is URL; urlString: (value: unknown) => asserts value is string; truthy: (value: unknown) => asserts value is unknown; falsy: (value: unknown) => asserts value is unknown; nan: (value: unknown) => asserts value is unknown; primitive: (value: unknown) => asserts value is Primitive; integer: (value: unknown) => asserts value is number; safeInteger: (value: unknown) => asserts value is number; plainObject: (value: unknown) => asserts value is Record; typedArray: (value: unknown) => asserts value is TypedArray; arrayLike: (value: unknown) => asserts value is ArrayLike; domElement: (value: unknown) => asserts value is Element; observable: (value: unknown) => asserts value is ObservableLike; nodeStream: (value: unknown) => asserts value is NodeStream; infinite: (value: unknown) => asserts value is number; emptyArray: (value: unknown) => asserts value is never[]; nonEmptyArray: (value: unknown) => asserts value is unknown[]; emptyString: (value: unknown) => asserts value is ''; nonEmptyString: (value: unknown) => asserts value is string; emptyStringOrWhitespace: (value: unknown) => asserts value is string; emptyObject: (value: unknown) => asserts value is Record; nonEmptyObject: (value: unknown) => asserts value is Record; emptySet: (value: unknown) => asserts value is Set; nonEmptySet: (value: unknown) => asserts value is Set; emptyMap: (value: unknown) => asserts value is Map; nonEmptyMap: (value: unknown) => asserts value is Map; // Numbers. evenInteger: (value: number) => asserts value is number; oddInteger: (value: number) => asserts value is number; // Two arguments. directInstanceOf: (instance: unknown, class_: Class) => asserts instance is T; inRange: (value: number, range: number | number[]) => asserts value is number; // Variadic functions. any: (predicate: Predicate | Predicate[], ...values: unknown[]) => void | never; all: (predicate: Predicate, ...values: unknown[]) => void | never; } export const assert: Assert = { // Unknowns. undefined: (value: unknown): asserts value is undefined => assertType(is.undefined(value), TypeName.undefined, value), string: (value: unknown): asserts value is string => assertType(is.string(value), TypeName.string, value), number: (value: unknown): asserts value is number => assertType(is.number(value), TypeName.number, value), bigint: (value: unknown): asserts value is bigint => assertType(is.bigint(value), TypeName.bigint, value), // eslint-disable-next-line @typescript-eslint/ban-types function_: (value: unknown): asserts value is Function => assertType(is.function_(value), TypeName.Function, value), null_: (value: unknown): asserts value is null => assertType(is.null_(value), TypeName.null, value), class_: (value: unknown): asserts value is Class => assertType(is.class_(value), AssertionTypeDescription.class_, value), boolean: (value: unknown): asserts value is boolean => assertType(is.boolean(value), TypeName.boolean, value), symbol: (value: unknown): asserts value is symbol => assertType(is.symbol(value), TypeName.symbol, value), numericString: (value: unknown): asserts value is string => assertType(is.numericString(value), AssertionTypeDescription.numericString, value), array: (value: unknown): asserts value is T[] => assertType(is.array(value), TypeName.Array, value), buffer: (value: unknown): asserts value is Buffer => assertType(is.buffer(value), TypeName.Buffer, value), nullOrUndefined: (value: unknown): asserts value is null | undefined => assertType(is.nullOrUndefined(value), AssertionTypeDescription.nullOrUndefined, value), object: (value: unknown): asserts value is object => assertType(is.object(value), TypeName.Object, value), iterable: (value: unknown): asserts value is Iterable => assertType(is.iterable(value), AssertionTypeDescription.iterable, value), asyncIterable: (value: unknown): asserts value is AsyncIterable => assertType(is.asyncIterable(value), AssertionTypeDescription.asyncIterable, value), generator: (value: unknown): asserts value is Generator => assertType(is.generator(value), TypeName.Generator, value), asyncGenerator: (value: unknown): asserts value is AsyncGenerator => assertType(is.asyncGenerator(value), TypeName.AsyncGenerator, value), nativePromise: (value: unknown): asserts value is Promise => assertType(is.nativePromise(value), AssertionTypeDescription.nativePromise, value), promise: (value: unknown): asserts value is Promise => assertType(is.promise(value), TypeName.Promise, value), generatorFunction: (value: unknown): asserts value is GeneratorFunction => assertType(is.generatorFunction(value), TypeName.GeneratorFunction, value), asyncGeneratorFunction: (value: unknown): asserts value is AsyncGeneratorFunction => assertType(is.asyncGeneratorFunction(value), TypeName.AsyncGeneratorFunction, value), // eslint-disable-next-line @typescript-eslint/ban-types asyncFunction: (value: unknown): asserts value is Function => assertType(is.asyncFunction(value), TypeName.AsyncFunction, value), // eslint-disable-next-line @typescript-eslint/ban-types boundFunction: (value: unknown): asserts value is Function => assertType(is.boundFunction(value), TypeName.Function, value), regExp: (value: unknown): asserts value is RegExp => assertType(is.regExp(value), TypeName.RegExp, value), date: (value: unknown): asserts value is Date => assertType(is.date(value), TypeName.Date, value), error: (value: unknown): asserts value is Error => assertType(is.error(value), TypeName.Error, value), map: (value: unknown): asserts value is Map => assertType(is.map(value), TypeName.Map, value), set: (value: unknown): asserts value is Set => assertType(is.set(value), TypeName.Set, value), weakMap: (value: unknown): asserts value is WeakMap => assertType(is.weakMap(value), TypeName.WeakMap, value), weakSet: (value: unknown): asserts value is WeakSet => assertType(is.weakSet(value), TypeName.WeakSet, value), int8Array: (value: unknown): asserts value is Int8Array => assertType(is.int8Array(value), TypeName.Int8Array, value), uint8Array: (value: unknown): asserts value is Uint8Array => assertType(is.uint8Array(value), TypeName.Uint8Array, value), uint8ClampedArray: (value: unknown): asserts value is Uint8ClampedArray => assertType(is.uint8ClampedArray(value), TypeName.Uint8ClampedArray, value), int16Array: (value: unknown): asserts value is Int16Array => assertType(is.int16Array(value), TypeName.Int16Array, value), uint16Array: (value: unknown): asserts value is Uint16Array => assertType(is.uint16Array(value), TypeName.Uint16Array, value), int32Array: (value: unknown): asserts value is Int32Array => assertType(is.int32Array(value), TypeName.Int32Array, value), uint32Array: (value: unknown): asserts value is Uint32Array => assertType(is.uint32Array(value), TypeName.Uint32Array, value), float32Array: (value: unknown): asserts value is Float32Array => assertType(is.float32Array(value), TypeName.Float32Array, value), float64Array: (value: unknown): asserts value is Float64Array => assertType(is.float64Array(value), TypeName.Float64Array, value), bigInt64Array: (value: unknown): asserts value is BigInt64Array => assertType(is.bigInt64Array(value), TypeName.BigInt64Array, value), bigUint64Array: (value: unknown): asserts value is BigUint64Array => assertType(is.bigUint64Array(value), TypeName.BigUint64Array, value), arrayBuffer: (value: unknown): asserts value is ArrayBuffer => assertType(is.arrayBuffer(value), TypeName.ArrayBuffer, value), sharedArrayBuffer: (value: unknown): asserts value is SharedArrayBuffer => assertType(is.sharedArrayBuffer(value), TypeName.SharedArrayBuffer, value), dataView: (value: unknown): asserts value is DataView => assertType(is.dataView(value), TypeName.DataView, value), urlInstance: (value: unknown): asserts value is URL => assertType(is.urlInstance(value), TypeName.URL, value), urlString: (value: unknown): asserts value is string => assertType(is.urlString(value), AssertionTypeDescription.urlString, value), truthy: (value: unknown): asserts value is unknown => assertType(is.truthy(value), AssertionTypeDescription.truthy, value), falsy: (value: unknown): asserts value is unknown => assertType(is.falsy(value), AssertionTypeDescription.falsy, value), nan: (value: unknown): asserts value is unknown => assertType(is.nan(value), AssertionTypeDescription.nan, value), primitive: (value: unknown): asserts value is Primitive => assertType(is.primitive(value), AssertionTypeDescription.primitive, value), integer: (value: unknown): asserts value is number => assertType(is.integer(value), AssertionTypeDescription.integer, value), safeInteger: (value: unknown): asserts value is number => assertType(is.safeInteger(value), AssertionTypeDescription.safeInteger, value), plainObject: (value: unknown): asserts value is Record => assertType(is.plainObject(value), AssertionTypeDescription.plainObject, value), typedArray: (value: unknown): asserts value is TypedArray => assertType(is.typedArray(value), AssertionTypeDescription.typedArray, value), arrayLike: (value: unknown): asserts value is ArrayLike => assertType(is.arrayLike(value), AssertionTypeDescription.arrayLike, value), domElement: (value: unknown): asserts value is Element => assertType(is.domElement(value), AssertionTypeDescription.domElement, value), observable: (value: unknown): asserts value is ObservableLike => assertType(is.observable(value), TypeName.Observable, value), nodeStream: (value: unknown): asserts value is NodeStream => assertType(is.nodeStream(value), AssertionTypeDescription.nodeStream, value), infinite: (value: unknown): asserts value is number => assertType(is.infinite(value), AssertionTypeDescription.infinite, value), emptyArray: (value: unknown): asserts value is never[] => assertType(is.emptyArray(value), AssertionTypeDescription.emptyArray, value), nonEmptyArray: (value: unknown): asserts value is unknown[] => assertType(is.nonEmptyArray(value), AssertionTypeDescription.nonEmptyArray, value), emptyString: (value: unknown): asserts value is '' => assertType(is.emptyString(value), AssertionTypeDescription.emptyString, value), nonEmptyString: (value: unknown): asserts value is string => assertType(is.nonEmptyString(value), AssertionTypeDescription.nonEmptyString, value), emptyStringOrWhitespace: (value: unknown): asserts value is string => assertType(is.emptyStringOrWhitespace(value), AssertionTypeDescription.emptyStringOrWhitespace, value), emptyObject: (value: unknown): asserts value is Record => assertType(is.emptyObject(value), AssertionTypeDescription.emptyObject, value), nonEmptyObject: (value: unknown): asserts value is Record => assertType(is.nonEmptyObject(value), AssertionTypeDescription.nonEmptyObject, value), emptySet: (value: unknown): asserts value is Set => assertType(is.emptySet(value), AssertionTypeDescription.emptySet, value), nonEmptySet: (value: unknown): asserts value is Set => assertType(is.nonEmptySet(value), AssertionTypeDescription.nonEmptySet, value), emptyMap: (value: unknown): asserts value is Map => assertType(is.emptyMap(value), AssertionTypeDescription.emptyMap, value), nonEmptyMap: (value: unknown): asserts value is Map => assertType(is.nonEmptyMap(value), AssertionTypeDescription.nonEmptyMap, value), // Numbers. evenInteger: (value: number): asserts value is number => assertType(is.evenInteger(value), AssertionTypeDescription.evenInteger, value), oddInteger: (value: number): asserts value is number => assertType(is.oddInteger(value), AssertionTypeDescription.oddInteger, value), // Two arguments. directInstanceOf: (instance: unknown, class_: Class): asserts instance is T => assertType(is.directInstanceOf(instance, class_), AssertionTypeDescription.directInstanceOf, instance), inRange: (value: number, range: number | number[]): asserts value is number => assertType(is.inRange(value, range), AssertionTypeDescription.inRange, value), // Variadic functions. any: (predicate: Predicate | Predicate[], ...values: unknown[]): void | never => assertType(is.any(predicate, ...values), AssertionTypeDescription.any, values), all: (predicate: Predicate, ...values: unknown[]): void | never => assertType(is.all(predicate, ...values), AssertionTypeDescription.all, values) }; // Some few keywords are reserved, but we'll populate them for Node.js users // See https://github.com/Microsoft/TypeScript/issues/2536 Object.defineProperties(is, { class: { value: is.class_ }, function: { value: is.function_ }, null: { value: is.null_ } }); Object.defineProperties(assert, { class: { value: assert.class_ }, function: { value: assert.function_ }, null: { value: assert.null_ } }); export default is; // For CommonJS default export support module.exports = is; module.exports.default = is; module.exports.assert = assert;