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Re: How to cast an imperative loop into a readable recursive function ?
From: |
Katalin Sinkov |
Subject: |
Re: How to cast an imperative loop into a readable recursive function ? |
Date: |
Thu, 2 Dec 2010 23:37:20 -0800 (PST) |
User-agent: |
G2/1.0 |
On Dec 2, 9:35 pm, "Pascal J. Bourguignon" <p...@informatimago.com>
wrote:
> Katalin Sinkov <lispstyl...@gmail.com> writes:
> > Take a look at my lisp code. it can be modified simply to run it and
> > it runs in an emacs "ide".
>
> No it does not.
>
> First, it's lacking a parenthesis.
>
> You should get paredit.el, and activate the paredit-mode to edit lisp
> sources. See how lisp code is indented, and let emacs and paredit
> indent it for you, and place the parentheses for you. This will produce
> lisp code that is more readable, and you will be able to copy-and-paste
> sexps "structurally", with much less risk of losing parentheses.
>
> Then, if we add the obvious missing parenthesis, and try to evaluate
> your code:
>
> (let ((char_skips (- n s) ))
> (while (not (= char_skips 0))
> (progn
> (if (<= char_skips (+ l -1) )
> (progn
> (forward-char char_skips)
> (setq char_skips 0))
> (progn
> (forward-char l)
>
> (forward-search-regexp "(s=###l=###)" nil nil nil) ; put in
> an if
> ;; and else block to test if FAIL
> (setq s (match-string 0))
> (setq l (match-string 0))
>
> (setq char_skips (- n s) ))))))
>
> we get the following error:
>
> Debugger entered--Lisp error: (void-variable n)
> (- n s)
> (let ((char_skips ...)) (while (not ...) (progn ...)))
> eval((let ((char_skips ...)) (while (not ...) (progn ...))))
> eval-last-sexp-1(nil)
> eval-last-sexp(nil)
> call-interactively(eval-last-sexp nil nil)
>
> If you want us to help, please provide working stand alone code, with
> test data.
>
> (By the way, my emacs "23.2.1" doesn't have a forward-search-regexp
> function).
search-forward-regexp
more later tomorrow
>
> --
> __Pascal Bourguignon__ http://www.informatimago.com/
> A bad day in () is better than a good day in {}.
- Re: How to cast an imperative loop into a readable recursive function ?, (continued)
Re: How to cast an imperative loop into a readable recursive function ?, RG, 2010/12/09