Why does Scala use a reversed shebang (!#) instead of just setting interpreter to scala

Question

The scala documentation shows that the way to create a scala script is like this:

#!/bin/sh
exec scala \"$0\" \"$@\"
!#
/* Script here */

I

Answer 1

How old is the documentation? Usually, this sort of thing (often referred to as 'the exec hack') was recommended before /bin/env was common, and this was the best way to get the functionality. Note that /usr/bin/env is more common than /bin/env, and ought to be used instead.