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ord.js
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/
ord.js
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module.exports = function ord(string) {
// discuss at: https://locutus.io/php/ord/
// original by: Kevin van Zonneveld (https://kvz.io)
// bugfixed by: Onno Marsman (https://twitter.com/onnomarsman)
// improved by: Brett Zamir (https://brett-zamir.me)
// input by: incidence
// example 1: ord('K')
// returns 1: 75
// example 2: ord('\uD800\uDC00'); // surrogate pair to create a single Unicode character
// returns 2: 65536
const str = string + ''
const code = str.charCodeAt(0)
if (code >= 0xd800 && code <= 0xdbff) {
// High surrogate (could change last hex to 0xDB7F to treat
// high private surrogates as single characters)
const hi = code
if (str.length === 1) {
// This is just a high surrogate with no following low surrogate,
// so we return its value;
return code
// we could also throw an error as it is not a complete character,
// but someone may want to know
}
const low = str.charCodeAt(1)
return (hi - 0xd800) * 0x400 + (low - 0xdc00) + 0x10000
}
if (code >= 0xdc00 && code <= 0xdfff) {
// Low surrogate
// This is just a low surrogate with no preceding high surrogate,
// so we return its value;
return code
// we could also throw an error as it is not a complete character,
// but someone may want to know
}
return code
}