72 lines
1.5 KiB
JavaScript
72 lines
1.5 KiB
JavaScript
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/**
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* @license Apache-2.0
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*
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* Copyright (c) 2018 The Stdlib Authors.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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'use strict';
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// MODULES //
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var ctors = require( './ctors.js' );
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// VARIABLES //
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var bool;
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// FUNCTIONS //
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/**
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* Returns a boolean indicating if an environment is little endian.
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*
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* @private
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* @returns {boolean} boolean indicating if an environment is little endian
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*
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* @example
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* var bool = isLittleEndian();
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* // returns <boolean>
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*/
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function isLittleEndian() {
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var uint16view;
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var uint8view;
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uint16view = new ctors[ 'uint16' ]( 1 );
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/*
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* Set the uint16 view to a value having distinguishable lower and higher order words.
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*
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* 4660 => 0x1234 => 0x12 0x34 => '00010010 00110100' => (0x12,0x34) == (18,52)
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*/
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uint16view[ 0 ] = 0x1234;
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// Create a uint8 view on top of the uint16 buffer:
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uint8view = new ctors[ 'uint8' ]( uint16view.buffer );
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// If little endian, the least significant byte will be first...
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return ( uint8view[ 0 ] === 0x34 );
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}
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// MAIN //
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bool = isLittleEndian();
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// EXPORTS //
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module.exports = bool;
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