colorized_input.rb

require "io/console"

COLORS = {
  black: 0,
  red: 31,
  green: 32,
  blue: 34
}

loop do
  print "❯ "
  command = ""

  loop do
    char = $stdin.getch

    break if char == "\r" # User pressed <enter>

    color = char == "e" ? COLORS[:red] : COLORS[:black] # Letter "e" will show up in red

    printf "\033[#{color}m#{char}\033[#{COLORS[:black]}m"
    command << char
  end

  break if command == "exit"

  puts
end