dynamically rename tags in hlwm using dmenu

dmenu_hlwm_rename_tags

#!/bin/bash

### License: GPL3+
#
# Author: Kyle Andrews
#
# This script enables dynamic creation of new tags in hlwm.
#
###

hc() {
    herbstclient "$@"
}

# return the first integer index of the value in the array
index_of() {
    local x="$1"
    local -n xs="${2}"
    for i in "${!xs[@]}"; do
	if [[ "${xs[$i]}" = "${x}" ]]; then
	    echo "${i}";
	    break
	fi
    done
}

print_array() {
    local -n xs="${1}"
    printf '%s\n' "${xs[@]}"    
}

eval $(hc tag_status | txr -B -c '	@(coll)@{status /[#:.]/}@{tag /[^\t]+/}@(end)')

ren=$(print_array tag | dmenu -i -p "rename tag:")
Mod=Mod4
idx=$(index_of "$ren" tag)
len=${#tag[@]}
keys=({1..9} 0)
if [[ ! -z $idx ]]
then
    new=$(echo "$ren" | dmenu -i -p "new tag name:")
    nidx=$(index_of "$new" tag)
    if [[ -z $nidx ]]
    then
        hc rename $ren $new
    fi
fi