Expand value of the variable name stored within another variable

[yperron]

Hello there,

I have the following variables defined in a script

set PKG_NAME=CORE
set MY_%PKG_NAME%_HOME=c:\home

So this creates a variable named MY_CORE_HOME (but I dont know that from within the script).
Then if I try to acces my variable using MY_%PKG_NAME%_HOME:

> echo MY_%PKG_NAME%_HOME
MY_CORE_HOME 

> echo %MY_%PKG_NAME%_HOME%
CORE

What should I do can to access the content of the MY_%PKG_NAME%_HOME and have for result c:\home ?

please help
thanks 

[contrex]

You cannot do this. Batch variables do not work in that way. You cannot hide a variable inside another.

@echo off
set PKG_NAME=CORE
set MY_%PKG_NAME%_HOME=c:\home
echo 1 MY_%PKG_NAME%_HOME
echo 2 %MY_%PKG_NAME%_HOME%
echo 3 %MY_CORE_HOME%

[/tt]

1 MY_CORE_HOME
2 PKG_NAME
3 c:\home

[/tt]

[gpl]

You need to invoke another level of nesting

call set MY_%PKG_NAME%_HOME=c:\home
call echo 1 MY_%PKG_NAME%_HOME

etc

what happens is that the %PKG_NAME% is evaluated and substituted into the expression

dont forget to double-up the %s inside a batch file
Graham

[contrex]

Nice catch Graham

[yperron]

so finally to transfer the content of the variable into a one that i can access at the first level I do:

>call set TEST=%MY_%PKG_NAME%_HOME%
>set TEST
TEST=c:\home

then I can use TEST directly for my manipulation!

Thanks

PS: I had to add % to get it work (see above)