How to expand a CMD shell variable twice (recursively)

Question

Using the Windows XP CMD command-line I can expand a variable twice as follows:

set AAA=BBB
set BBB=CCC
for /F \"usebackq tokens=*\" %i in (`echo %%AAA%%`) d         


        

Answer 1

How to expand a shell variable multiple times:

@echo off
setlocal enabledelayedexpansion

set myvar=second
set second=third
set third=fourth
set fourth=fifth

echo Variable value before expansion: !myvar!
call :expand myvar
echo Variable value after expansion: !myvar!
goto :eof


:expand
    set var=%1
    :expand_loop
        if not "!%var%!" == "" (
            set var=!%var%!
            goto :expand_loop
        )
        set %1=!var!
    goto :eof

output:

Variable value before expansion: second
Variable value after expansion: fifth