#!/bin/bash

date | tr [:upper:] [:lower:]
date | tr [:upper:] "[:lower:]"
date | tr [:upper:] '[:lower:]'
date | tr '[:upper:]' [:lower:]
date | tr "[:upper:]" [:lower:]
date | tr '[:upper:]' '[:lower:]'
date | tr "[:upper:]" "[:lower:]"
echo Aa | tr -d [:lower:]
echo Aa | tr -d [:upper:]
ucr_varname="$(echo "$name" | tr [A-Z] [a-z] | sed 's| ||g')"
ucr_varname="$(echo "$name" | tr "[A-Z]" [a-z] | sed 's| ||g')"
ucr_varname="$(echo "$name" | tr '[A-Z]' [a-z] | sed 's| ||g')"
echo Aa | tr -d "[:lower:]"
echo Aa | tr -d "[:upper:]"
ucr_varname="$(echo "$name" | tr "[A-Z]" "[a-z]" | sed 's| ||g')"
echo Aa | tr -d '[:lower:]'
echo Aa | tr -d '[:upper:]'
ucr_varname="$(echo "$name" | tr '[A-Z]' '[a-z]' | sed 's| ||g')"
ucr_varname="$(echo "$name" | tr '[A-Z]' "[a-z]" | sed 's| ||g')"
ucr_varname="$(echo "$name" | tr "[A-Z]" '[a-z]' | sed 's| ||g')"
date | tr [[:upper:]] [[:lower:]]
date | tr "[[:upper:]]" [[:lower:]]
date | tr "[[:upper:]]" "[[:lower:]]"
date | tr '[[:upper:]]' '[[:lower:]]'
