Yes, that is the idea of #DEFINE constants - that they are evaluated at compile time. They are replaced in the program before the main phase of the compilation. For instance, if you use:

#DEFINE MAX_USERS 100

Then the compiled file will not have any variable MAX_USERS; instead, it will have the value 100 everywhere you had used MAX_USERS.

For the need you describe, you should use a variable, not a #DEFINE.

>Hi,
>Is constant evaluated only during compile time?
>
>At first, I hardcoded my application folder as constant.
>
>

>#DEFINE   APPFOLDER      "C:\myproject\"
>#DEFINE   MYPRGFOLDER    APPFOLDER + "PRGS"
>
>?MYPRGFOLDER     && Show C:\myproject\PRGS
>

>
>Then, I changed my code to allow user to specify app folder during runtime. So I changed code as below.
>
>

>**#DEFINE   APPFOLDER      "C:\myproject\"
>#DEFINE   MYPRGFOLDER    APPFOLDER + "PRGS"
>
>LOCAL APPFOLDER
>
>APPFOLDER = ADDBS(GETDIR())    && User select "C:\MYPROJECT2\"
>?MYPRGFOLDER     && It shows C:\myproject2\PRGS too!!!!
>

>
>I was thinking constant only been evaluated during compile time.
>
>Please advice.