Press n or j to go to the next uncovered block, b, p or k for the previous block.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 | 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x | /**
* @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 isString = require( '@stdlib/assert/is-string' ).isPrimitive;
var format = require( '@stdlib/string/format' );
// VARIABLES //
// '\ufeff' => 1111111011111111 => 0xFEFF => 65279
var BOM = 65279;
// MAIN //
/**
* Removes a UTF-8 byte order mark (BOM) from the beginning of a string.
*
* ## Notes
*
* - A UTF-8 byte order mark ([BOM][1]) is the byte sequence `0xEF,0xBB,0xBF`.
* - To convert a UTF-8 encoded `Buffer` to a `string`, the `Buffer` must be converted to [UTF-16][2]. The BOM thus gets converted to the single 16-bit code point `'\ufeff'` (UTF-16 BOM).
*
* [1]: https://en.wikipedia.org/wiki/Byte_order_mark#UTF-8
* [2]: http://es5.github.io/#x4.3.16
*
* @param {string} str - input string
* @throws {TypeError} must provide a string primitive
* @returns {string} string with BOM removed
*
* @example
* var str = removeUTF8BOM( '\ufeffbeep' );
* // returns 'beep'
*/
function removeUTF8BOM( str ) {
if ( !isString( str ) ) {
throw new TypeError( format( 'invalid argument. Must provide a string. Value: `%s`.', str ) );
}
if ( str.charCodeAt( 0 ) === BOM ) {
return str.slice( 1 );
}
return str;
}
// EXPORTS //
module.exports = removeUTF8BOM;
|