time-to-botec/squiggle/node_modules/@stdlib/assert/is-little-endian/lib/main.js

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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 ctors = require( './ctors.js' );
// VARIABLES //
var bool;
// FUNCTIONS //
/**
* Returns a boolean indicating if an environment is little endian.
*
* @private
* @returns {boolean} boolean indicating if an environment is little endian
*
* @example
* var bool = isLittleEndian();
* // returns <boolean>
*/
function isLittleEndian() {
var uint16view;
var uint8view;
uint16view = new ctors[ 'uint16' ]( 1 );
/*
* Set the uint16 view to a value having distinguishable lower and higher order words.
*
* 4660 => 0x1234 => 0x12 0x34 => '00010010 00110100' => (0x12,0x34) == (18,52)
*/
uint16view[ 0 ] = 0x1234;
// Create a uint8 view on top of the uint16 buffer:
uint8view = new ctors[ 'uint8' ]( uint16view.buffer );
// If little endian, the least significant byte will be first...
return ( uint8view[ 0 ] === 0x34 );
}
// MAIN //
bool = isLittleEndian();
// EXPORTS //
module.exports = bool;