Type Check

Collection of small javascript type check functions.

Installation via NPM or Yarn

npm install -D @spaceavocado/type-check or yarn add @spaceavocado/type-check -D

Usage

The library is built as Exported as CommonJS module and as ESM module.

Import All Functions

import tc from '@spaceavocado/type-check';
tc.isFunction(value);

The tc object has not property which holds negated version of all functions. e.g. tc.isString(), tc.not.isString().

Specific Functions

import {isFunction, isArray} from '@spaceavocado/type-check';

Type Check Functions

isString

tc.isString('value');
// => true

tc.not.isString('value');
// => false

isEmpty

Supports string and array empty check, any other types throws an error (tc.TypeCheckError).

// String value
tc.isEmpty('');
// => true

// Array value
tc.isEmpty([]);
// => true

tc.isEmpty({});
// => throws tc.TypeCheckError

// String value
tc.not.isEmpty('');
// => false

// Array value
tc.not.isEmpty([]);
// => false

isNumber

tc.isNumber(5);
// => true

tc.not.isNumber(5);
// => false

isFunction

tc.isFunction(() => {});
// => true

tc.not.isFunction(() => {});
// => false

isObject

tc.isObject({});
// => true

tc.not.isObject({});
// => false

isError

tc.isError(new Error('error message'));
// => true

tc.not.isError(new Error('error message'));
// => false

isNullOrUndefined

tc.isNullOrUndefined(undefined);
// => true

tc.isNullOrUndefined(null);
// => true

tc.not.isNullOrUndefined(undefined);
// => false

isArray

tc.isArray([]);
// => true

tc.not.isArray([]);
// => false

isSymbol

tc.isSymbol(new Symbol());
// => true

tc.not.isSymbol(new Symbol());
// => false

isPromise

tc.isPromise(new Promise((resolve, reject) => {}));
// => true

tc.not.isPromise(new Promise((resolve, reject) => {}));
// => false

isEnumKey

const myEnum = {
  A: 'A',
  B: 'B',
}

tc.isEnumKey(myEnum.A, myEnum);
// => true

tc.isEnumKey('C', myEnum);
// => false

tc.not.isEnumKey(myEnum.A, myEnum);
// => false

License

Svelte Router is released under the MIT license. See LICENSE.txt.