Hi!
Nice to know of identifier-syntax.
It looks useful once you understand how it works.
I also found it is faster than delay/force,
the functions are different though.
Well, nonetheless, there still are some overheads,
assigning variables, and cheking them if they are new.
What I want is no
Hi,
Thanks for many examples!
At Thu, 17 Nov 2005 17:31:06 -,
Thomas Chust wrote:
For example
(lazy-let ((a (get-a)))
(let ((a (get-something-else)))
(if (condition) a #f)))
always evaluates (get-a) even though it is never needed, because it
macroexpands into
(begin
At Fri, 18 Nov 2005 08:18:11 +0900, Daishi Kato wrote:
Would it be worth improving the lazy-let macro
so that it understands at least let and quote forms?
Not let forms. Analyzing subforms of a macro is called code-walking,
and the first thing you then need to do is sc-expand the body or
Thanks, Tohmas and Alex!
I think I understand that simple code-walking does not help,
in many cases, for example, a loop.
(lazy-let ((a (get-a)))
(letrec ([b (lambda () (when (condition) (print a) (b)))])
(b)))
OK, I would not need a general solution,
let me think about it for a
Am 16.11.2005, 09:18 Uhr, schrieb Daishi Kato [EMAIL PROTECTED]:
[...]
Does anyone know of any existence of a lazy-let macro,
which does the following?
convert from
(lazy-let ([a (get-a)][b (get-b)])
(if (condition) a b))
into
(if (condition) (get-a) (get-b))
[...]
Hello,
I haven't
Hi,
I have first considered the use of delay/force,
but it turns out that it is a little bit costly.
So, I want it to be done at the complie time.
This should probablly be called let-ahead instead of lazy-let.
Anyway, your macro example is helpful to me.
Let me think again.
Thanks,
Daishi
At
At Wed, 16 Nov 2005 18:18:00 +0900, Daishi Kato wrote:
Does anyone know of any existence of a lazy-let macro,
which does the following?
convert from
[...]
(lazy-let ([a (get-a)][b (get-b)])
(if (condition)
(begin (display a) a)
(begin (display b) b)))
into
(if
