From mboxrd@z Thu Jan  1 00:00:00 1970
To: 9fans@cse.psu.edu
From: Ralph Corderoy <ralph@inputplus.co.uk>
Message-ID: <18a0.3ed2038a.929e4@blake.inputplus.co.uk>
References: <20030501160047.7231.qmail@g.bio.cse.psu.edu>, <20030507124006.D26796@cackle.proxima.alt.za>
Subject: Re: [9fans] same functions everywhere
Date: Tue, 27 May 2003 09:22:29 +0000
Topicbox-Message-UUID: b9303a4e-eacb-11e9-9e20-41e7f4b1d025

Hi Lucio,

> I don't go along with that.  Consider the conventional linear search
> of an array:
>
> 	int a[100];
> 	int x, v;
>
> 	...
>
> 	x = 0;
> 	while (x < 100 && a[x] != v) {
> 		++x;
> 	}
>
> (or whatever version you prefer).
>
> At the end, you always have to determine whether you found the desired
> element or exceeded the array bounds.
> ...
> This particular problem has bugged me for decades :-)  I go along with
> Doug that exception handling can hide the extremely uninteresting code
> involved in dealing with rare or "off band" conditions.

Python solves this particular problem like this:

    a = [1, 2, 3]

    for x in range(len(a)):
        if a[x] == 42:
            print x
            break
    else:
        print -1

The for's else clause is only executed if a natural end to the loop is
reached, i.e. you don't break out of it.

Cheers,

--
Ralph Corderoy.      http://inputplus.co.uk/ralph/     http://troff.org/