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* @license Apache-2.0
*
* Copyright (c) 2018 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
'use strict';
// MODULES //
var hasHasInstanceSymbolSupport = require( '@stdlib/assert/has-has-instance-symbol-support' ); // eslint-disable-line id-length
var HasInstanceSymbol = require( '@stdlib/symbol/has-instance' );
var format = require( '@stdlib/string/format' );
// VARIABLES //
var hasSupport = hasHasInstanceSymbolSupport();
// MAIN //
/**
* Tests whether a value has in its prototype chain a specified constructor as a prototype property.
*
* @param {*} value - value to test
* @param {Function} constructor - constructor to test against
* @throws {TypeError} constructor must be callable
* @returns {boolean} boolean indicating whether a value is an instance of a provided constructor
*
* @example
* var bool = instanceOf( [], Array );
* // returns true
*
* @example
* var bool = instanceOf( {}, Object ); // exception
* // returns true
*
* @example
* var bool = instanceOf( 'beep', String );
* // returns false
*
* @example
* var bool = instanceOf( null, Object );
* // returns false
*
* @example
* var bool = instanceOf( 5, Object );
* // returns false
*/
function instanceOf( value, constructor ) {
// TODO: replace with `isCallable` check
if (
typeof constructor !== 'function' &&
!(
hasSupport &&
typeof constructor === 'object' &&
typeof constructor[ HasInstanceSymbol ] === 'function'
)
) {
throw new TypeError( format( 'invalid argument. Second argument must be callable. Value: `%s`.', constructor ) );
}
return ( value instanceof constructor );
}
// EXPORTS //
module.exports = instanceOf;
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