Re: Capturing a function in a closure

In article <slrng8cdk5.h0c.gwillen@[EMAIL PROTECTED]
>,
 Glenn Willen <gwillen@[EMAIL PROTECTED]
> wrote:

> In article <6emqgpF7pnpkU1@[EMAIL PROTECTED]
>, Pascal Costanza wrote:
> > Yes, this is a terrible hack. It's ugliness will manifest itself when 
> > you attempt to file-compile code with such references:
> > 
> > (defun foo (x) x)
> > 
> > (defun bar (x) (apply #.#'foo (list x)))
> > 
> > If you file-compile such code, the compiler will complain because the 
> > function foo is not defined yet at readtime.
> 
> Right, this is why I emphasized read-time. What I really want to capture
is
> function-definition-evaluation-time. Unfortunately I've done very little
> working with or thinking about compilation versus interpretation, which
means
> there are more 'times' than I'm really comfortable with.
> > 
> > What you want is load-time-value:
> > 
> > (defun foo (x) x)
> > 
> > (defun bar (x) (apply (load-time-value #'foo) (list x)))
> 
> Interesting! That's a form I've never heard of before.

On the Lisp Machine one could display a random hint with a command.
I propose a random CLHS page of the day. The Hyperspec has
a file with links for each Common Lisp symbol.  One could for example
email a clhs html file for a random CL symbol each day. After
a few years you can then start over... ;-) Planet Lisp
could also display the CLHS symbol of the day. Etc...

> The CLHS suggests it is
> indeed precisely what I was looking for. Is "load time" always the same
as the
> time at which the function definition is evaluated? (I guess in the
compiled
> universe, there's no such time, just the time at which it's compiled and
the
> time at which the image is loaded, this being the latter. In the
interpreted
> universe I guess "load-time" is treated as precisely what I want,
though.)

Also make sure you read the entry for FUNCTION. (function foo) is
the expanded version of #'foo).

http://www.lispworks.com/do***entation/HyperSpec/Body/s_fn.htm

> 
> Thanks a lot!
> gwillen

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