Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!think.com!snorkelwacker.mit.edu!bloom-beacon!eru!hagbard!sunic!mcsun!ukc!newcastle.ac.uk!turing!ncmh
From: Chris.Holt@newcastle.ac.uk (Chris Holt)
Newsgroups: comp.object
Subject: Re: Documenting OO Systems
Keywords: operators
Message-ID: <1991Apr2.225553.13893@newcastle.ac.uk>
Date: 2 Apr 91 22:55:53 GMT
References: <jls.669768656@rutabaga> <299@orbit.gtephx.UUCP> <1991Mar25.145441.1@happy.colorado.edu> <20106@alice.att.com> <3481@engadm3.csd.mot.com> <DWWX.91Mar25215016@cbnewsk.ATT.COM> <jls.669956827@rutabaga> <1991Mar26.191259.14470@i88.isc.com> <4693@osc.COM> <jl
Sender: news@newcastle.ac.uk
Organization: University of Newcastle upon Tyne, UK, NE1 7RU
Lines: 30

horvath@motcid.UUCP (Bob Horvath) writes:
>pallas@eng.sun.com (Joseph Pallas) writes:

>-int j (int year, int month, int day) {
>-int month_days[12] = {31,28,31,30,31,30,31,31,30,31,30,31};
>-if (month<1 || month>12) return 0;
>-int leap = !(year%4) && year&400;
>-if (day<1 || day>(month_days[month-1] + (month==2 && year))) return 0;
>-int dayofmonth = 0;
>-for (int i=0; i<month-1; i++) dayofmonth += month_days[i];
>-return dayofmonth + day + (month>2 && year);
>-}

>Having read the rest of the posts I now know what it does.  Reading it with the
>variables changed gave me a clue that it did something with days, months, and
>years and the amount of days in a month. But not being a regular C programmer,
>I still wasn't able to *quickly* figure out exactly what it was doing.

I couldn't be bothered with the original version, and again having
read the posts I know what it does.  But *why* should it ever return
0, rather than some bottom value or exception?  It seems to me we've
got a language with pretty poor typing facilities :-).

Arr, Jim lad; I remember when we used less than 0 for the first branch,
0 for the second, and greater than 0 for the third.  That were
intuitively obvious, that were.
-----------------------------------------------------------------------------
 Chris.Holt@newcastle.ac.uk      Computing Lab, U of Newcastle upon Tyne, UK
-----------------------------------------------------------------------------
 "And when they die by thousands why, he laughs like anything." G Chesterton