On Wed, Jan 14, 2009 at 10:48 AM, Jonathan Cast
<jonathancc...@fastmail.fm> wrote:
> Do you have an example of
> a macro that can't be replaced by higher-order functions and laziness?
I believe I do: one macro I found useful when writing a web app in
Lisp was something I called hash-bind, which binds variables to the
values in a hashtable, with the variable names as keys. For example:
(hash-bind (a b) hashtable body)
==
(let
((a (lookup hashtable "a"))
(b (lookup hashtable "b"))
body)
I found this very useful in places where I was given URL request
parameters in a hashtable and wanted to extract some variables from
it. I don't believe it can be replaced by a higher order function
(though I may be wrong).
--Max
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