Rainbow colored bash prompt PS1 string

lolps1.bash

lolps1() {
    PREV_EXIT_CODE=$?
    # PS1 rainbow modified from https://gist.github.com/duckythescientist/8338f028e018fd3fecae58e4f1c45def
    # Replace $HOME with ~
    mypwd=${PWD/#$HOME/"~"}
    # Make a persistent, incrementing seed to make a smooth rainbow effect from line to line
    if [ -z ${LOLCAT_SEED+x} ]; then LOLCAT_SEED=1; else let "LOLCAT_SEED += 1"; fi
    PS1=$(echo " $mypwd" | lolcat --force --freq 0.3 --seed $LOLCAT_SEED 2>/dev/null)
    # Strip the "reset colors to normal" commands
    PS1=$(echo "$PS1" | sed $'s/\033\[0m//g')
    # Replace escape sequences with [escaped escape sequences]
    # e.g.: \[\033[38;5;39m\]
    PS1=$(echo "$PS1" | sed -r $'s/\033''(\[[0-9]+;[0-9]+;[0-9]+m)/\\\[\\033\1\\\]/g')
    # change the color back to white and add the $/# PS1 character
    PS1="${PS1}\[\033[0m\]\$ "
    # Prepend status indicator (based on https://twitter.com/lunasorcery/status/1433555199952519168)
    PS1="\[\033[0;$[91+($PREV_EXIT_CODE==0)]m\]●\[\033[0m\]"$PS1
}

PROMPT_COMMAND=lolps1