Colors matched lined such that the same matches have the same color

greco

#!/bin/bash

pattern="$1"

while IFS= read -r line
do
  if ! matchpart="$(grep -o "$pattern" <<<"$line")"
    then printf "%s\n" "$line"; continue
  fi
  rstr="$(printf "%s\n" "$matchpart" | head -n 1 | md5sum | head -c 6)"
  rgb=( $((echo 'ibase=16'; echo "${rstr^^}" | grep -o '..' | sed 's|.*| ( \0 + 10 ) * 10 / 11 |') | bc) )
  printf '\033[38;2;%d;%d;%dm%s\033[0m\n' "${rgb[0]}" "${rgb[1]}" "${rgb[2]}" "$line"
done