[REBOL] Re: Declaring variables (or words or whatever)
From: greggirwin:mindspring at: 3-Jun-2003 14:30
Hi Steven,
SW> I'm having a terrible time getting out of my old ways of thinking.
SW> If I want to declare a variable, just because I like to do things that
SW> way because it helps me keep track of things, which of these ways is
SW> recommended, or they equivalent?
SW> TP-FILE-ID: make file! %TPLAYER.DAT ;;; (number one)
SW> ... or ...
SW> make file! TP-FILE-ID: %TPLAYER.DAT ;;; (number two)
SW> ... or ...
SW> TP-FILE-ID: %TPLAYER.DAT ;;; (number three)
SW> They all seem to work, that is, if I "print TP-FILE-ID" I get the same
SW> results, but is one better/more efficient/recommended/better style
SW> etc.?
I'd use #3 for all general cases. While I don't agree *entirely* with
the Agile motto of "Do the simplest thing possible", in this case it
works. REBOL understands the value directly, so there is no need to do
anything special.
In #2 you're just discarding the value returned by MAKE, so it's
entirely redundant.
Now, #1 doesn't behave exactly like #3, so that's the other thing to
consider, and what is one of the hardest things to remember about
REBOL when coming from other languages. How you define values, and how
you use them, needs to be considered. E.g.
print f-1: make file! f-2: f-3: %TPLAYER.DAT
f-4: %TPLAYER.DAT
print equal? f-1 f-2
print same? f-1 f-2
print same? f-2 f-3
print same? f-2 f-4
append f-2 "XXX"
print [f-1 f-2 f-3 f-4]
-- Gregg
