time-to-botec/squiggle/node_modules/@stdlib/utils/nonindex-keys/lib/main.js
NunoSempere b6addc7f05 feat: add the node modules
Necessary in order to clearly see the squiggle hotwiring.
2022-12-03 12:44:49 +00:00

82 lines
1.6 KiB
JavaScript

/**
* @license Apache-2.0
*
* Copyright (c) 2019 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 objectKeys = require( './../../keys' );
// VARIABLES //
var RE_INTEGER_INDEX = /^[0-9]+$/;
// MAIN //
/**
* Returns an array of an object's own enumerable property names which are not integer indices.
*
* @param {ObjectLike} obj - input object
* @returns {Array} key array
*
* @example
* function Foo() {
* this[ 0 ] = 3.14;
* this.beep = 'boop';
* return this;
* }
*
* Foo.prototype.foo = 'bar';
*
* var obj = new Foo();
*
* var keys = nonIndexKeys( obj );
* // e.g., returns [ 'beep' ]
*/
function nonIndexKeys( obj ) {
var keys;
var len;
var N;
var i;
var j;
keys = objectKeys( obj );
len = keys.length;
N = len;
j = 0;
// Compress the list of keys by using a lagging index and moving non-integer indices to earlier positions in the array...
for ( i = 0; i < len; i++ ) {
if ( RE_INTEGER_INDEX.test( keys[ i ] ) ) {
N -= 1;
} else {
keys[ j ] = keys[ i ];
j += 1;
}
}
keys.length = N;
return keys;
}
// EXPORTS //
module.exports = nonIndexKeys;