Re: Newbie Design Question

From: Frode Vatvedt Fjeld (frodef_at_cs.uit.no)
Date: 11/23/03 

Date: Sun, 23 Nov 2003 10:50:18 +0100

jmkatcher@yahoo.com (Jeff Katcher) writes:

> I'm back to LISP after having been away for a long, long time (it's
> _hard_ to break the SETQ habit :).

Welcome back. And please, try at least as hard to lose the dangling
parens. Indentation is the visual code-block delimiter in Lisp, and
the parens merely tell your editor how to indent things. And a
paren-aware editor /is/ essential.

> Anyway, I have a function in my current program which is a planner
> of sorts. It takes a list of stuff as a parameter and builds lists
> of candidates for action.

I wasn't able to understand much from your pseudo-code, but from this
description it seems to me that what you'd want is something like

  (remove-if (complement #'eligible-p) stuff-list :start start :end end)

Or, if you need more control:

  (loop for stuff in stuff-list as position upfrom 0
     when (and (eligible-p stuff)
               (blabla stuff start))
     collect (figure-out-action stuff position))

Perhaps if you explain why this doesn't work, we can help you more. 

-- 
Frode Vatvedt Fjeld

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