These are examples in ZILF, but…
This was done alot in Mini-Zork II. If you look at the bottom of GLOBALS.ZIL you’ll see how it’s done there.
Note that if you can you should use GLOBALs (saves one byte extra) instead of CONSTANTs. The downside is that GLOBALs are a limited resource.
There is also a discussion here and here for doing this automatically for the ZILF compiler.