-tput_rev=${nocolor:-$(tput rev)}
-tput_sgr0=${nocolor:-$(tput sgr0)}
-tput_bold=${nocolor:-$(tput bold)}
-tput_setaf_0=${nocolor:-$(tput setaf 0)}
-tput_setaf_2=${nocolor:-$(tput setaf 2)}
+readonly tput_rev=${nocolor:-$(tput rev)}
+readonly tput_sgr0=${nocolor:-$(tput sgr0)}
+readonly tput_bold=${nocolor:-$(tput bold)}
+readonly tput_setaf_0=${nocolor:-$(tput setaf 0)}
+readonly tput_setaf_1=${nocolor:-$(tput setaf 1)}
+readonly tput_setaf_2=${nocolor:-$(tput setaf 2)}
+readonly tput_setaf_3=${nocolor:-$(tput setaf 3)}