Enhancement: set a string variable at build time (similar to go ld's -X flag)

[imbaczek]

Would it be possible to add functionality like go ld has? (Or maybe it's already possible and my google-fu fails me...?) This would be quite useful in Makefiles, build recipes, etc.

-X symbol value
    Set the value of an otherwise uninitialized string variable.
    The symbol name should be of the form importpath.name,
    as displayed in the symbol table printed by "go tool nm".

http://golang.org/cmd/ld/

Example usage: http://stackoverflow.com/a/11355611/38749

go build -ldflags "-X main.minversion `date -u +.%Y%m%d%.H%M%S`" service.go

main.minversion gets set to the build date and time.

[sfackler]

You can do this via environment variables and the env! macro:

static VERSION: &'static str = env!("VERSION");

env VERSION="1.0.32" rustc lib.rs

[steveklabnik]

Yes, you can. Giving this a close.