[REBOL] Re: lisp-like backquotes macros
From: gabriele:colellachiara at: 26-Nov-2005 11:46
Hi Henri,
On Saturday, November 26, 2005, 12:49:43 AM, you wrote:
HM> `[ ,value1 to-string ( to-integer ,value2 ) + 2 ]
Probably Ladislav's BUILD will help; anyway, sometimes it is
possible to refactor your code so that you don't need it.
In the case above, for example, you could write:
compose [(value1) to-string 2 + (to-integer value2)]
(Well, actually, in this specific case you could just write:
reduce [value1 to-string 2 + to-integer value2]
because there's no reason to do the add and the string conversion
at "runtime", but I assume it's just because this is a simplified
example.)
Also, REBOL offers another way to obtain the same goal without
composing at all.
use [value1' value2'] [
value1': value1
value2': to-integer value2
[value1' to-string value2' + 2]
]
Using a function like my LOCALIZE in:
http://www.colellachiara.com/soft/Libs/utility.r
localize [value1 value2] [
[value1 to-string 2 + to-integer value2]
]
The solutions here do not solve all the cases, especially when you
are composing PARSE rules; but they can give you ideas.
Regards,
Gabriele.
--
Gabriele Santilli <gabriele-rebol.com> --- http://www.rebol.com/
Colella Chiara software division --- http://www.colellachiara.com/
