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generate random v4 UUIDs (107 bytes)

# UUID

Returns a random v4 UUID of the form `xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx`, where each `x` is replaced with a random hexadecimal digit from 0 to f, and `y` is replaced with a random hexadecimal digit from 8 to b.

Instance, based on recursion, can be found here.

 function( a,b // placeholders ){ for( // loop :) b=a=''; // b - result , a - numeric variable a++<36; // b+=a*51&52 // if "a" is not 9 or 14 or 19 or 24 ? // return a random number or 4 ( a^15 // if "a" is not 15 ? // genetate a random number from 0 to 15 8^Math.random()* (a^20?16:4) // unless "a" is 20, in which case a random number from 8 to 11 : 4 // otherwise 4 ).toString(16) : '-' // in other cases (if "a" is 9,14,19,24) insert "-" ); return b }
 function(a,b){for(b=a='';a++<36;b+=a*51&52?(a^15?8^Math.random()*(a^20?16:4):4).toString(16):'-');return b}
 DO WTF YOU WANT TO PUBLIC LICENSE Version 2, December 2004 Copyright (C) 2011 Alexey Silin Everyone is permitted to copy and distribute verbatim or modified copies of this license document, and changing it is allowed as long as the name is changed. DO WTF YOU WANT TO PUBLIC LICENSE TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 0. You just DO WTF YOU WANT TO.
 { "name": "UUID", "description": "Generates random UUIDs", "contributors": [ "jed", "subzey", "tsaniel" ], "keywords": [ "UUID", "ID", "random" ] }