21 lines
		
	
	
		
			558 B
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			21 lines
		
	
	
		
			558 B
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| 'use strict';
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| 
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| // https://mathiasbynens.be/notes/javascript-encoding
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| // https://github.com/bestiejs/punycode.js - punycode.ucs2.decode
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| module.exports = function ucs2length(str) {
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|   var length = 0
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|     , len = str.length
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|     , pos = 0
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|     , value;
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|   while (pos < len) {
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|     length++;
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|     value = str.charCodeAt(pos++);
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|     if (value >= 0xD800 && value <= 0xDBFF && pos < len) {
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|       // high surrogate, and there is a next character
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|       value = str.charCodeAt(pos);
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|       if ((value & 0xFC00) == 0xDC00) pos++; // low surrogate
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|     }
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|   }
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|   return length;
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| };
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