Rob King deadpixi

UUIDv4 Generation in Three Different Array Languages

Here we see the same UUIDv4 generation function written in three different APL(-like) languages: APL, J, and K.

The algorithm is very simple, but one that lends itself well to implementation in an array language:

Generate a list of 36 random numbers between 0 and 15.
Transform each of those digits into a single-character string of the corresponding hex digit.
Join those characters together into a 36-character string.
Replace some of the characters with dashes.
Replace the character representing the version nybble with 4 (to indicate a version 4 UUID).
Constrain the character whose top two bits represent the variant to one that indicates the UUID is an RFC4122 UUID.

	#include <math.h>
	#include <stdint.h>
	#include <stdlib.h>
	#include <stdbool.h>
	#include <string.h>

	#include "thebe.h"

	/*** TODO
	* - switch tables to use uint32_t indexes; that's big enough for anybody, maybe even consider using

	#!/usr/bin/env python3

	import sys
	from typing import Dict, List, Optional


	class Game:
	def __init__(self, initial_location: "Room") -> None:
	self.location: Room = initial_location
	self.inventory: Dict[str, Item] = {}

	/* A UUIDv4 generator.
	* By [email protected]
	* This should work with any ANSI REXX interpreter,
	* and I think it would work with ARexx, but I
	* haven't checked.
	*/

	/* Store the 16 bytes of random data in a string called bits
	* We will populate this using either using the RANDOM function
	* or by reading from /dev/random, whichever the user requests.

	/* Copyright (c) 2013 Gianni Tedesco
	* Released under the terms of the GNU GPL version 3
	* mmap() packet socket transmission
	*/

	#ifndef __linux__
	#error "Are you loco? This is Linux only!"
	#endif

	#include <stdio.h>