[ BASH ] compute cartesian product of input variable length vectors with space separated elements

cartesian_product.sh

##################################################################################
# The MIT License (MIT)
#
# Copyright (c) 2015 Bertrand Martel
#
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# THE SOFTWARE.
###################################################################################
#!/bin/bash
#title         : cartesian_product.sh
#author		     : Bertrand Martel
#date          : 27/11/2015
#description   : compute cartesian product of input variable length vectors
#usage         : ./cartesian_product.sh <vector1> <vector2> .... <vectorn>
#usage exemple : ./cartesian_product.sh "a b c d e f g h i" "1 2 3 4 5 6 7 8 9" "a1 b2 b3 b4 b5 b6"
############################################################################
#!/bin/bash

function iterate {

	local index="$2"

	if [ "${index}" == "${#dim[@]}" ]; then

		for (( i=0; i<=${index}; i++ ))
		do
			echo -n "${items[$i]} "
		done
		echo ""
	else
		for element in ${dim[${index}]}; do
			items["${index}"]="${element}"
			local it=$((index+1))
			iterate items[@] "$it"
		done
	fi
}

if [ "$1" != "" ]; then

	declare -ag dim
	count=0

	for arguments in "$@"
	do
		dim["$count"]="$arguments"
		count=$((count+1))
	done
	
	declare -a items=("")
	
	iterate "" 0

fi