NetNews Usenet Archive 1992 #27/NN_1992_27.iso/spool/comp/lang/cplus/16556

Text File | 1992-11-19 | 1.4 KB | 32 lines

Newsgroups: comp.lang.c++
Path: sparky!uunet!cs.utexas.edu!zaphod.mps.ohio-state.edu!rpi!utcsri!helios.physics.utoronto.ca!alchemy.chem.utoronto.ca!mbersohn
From: [e-mail] (M. Bersohn)
Subject: RUN TIME ARRAY INDEX ERRORS
Message-ID: <[e-mail]>
Sender: [e-mail] (M. Bersohn)
Organization: University of Toronto Chemistry Department
Date: Thu, 19 Nov 1992 10:22:58 GMT
Lines: 21

Hello experienced people!
     There seem to be two ways to detect array index errors at
run time. One is to explicitly check the index.
int x[20];

if (j >= 0 && j < 20 && function1(x[j]))
    ...
     The other way is the C++ way,to overload the [] operator.
     Explicit checks clutter the code enormously. The operator
overloading method is transparent to us unless we remember the
class definition. It's neat.
     My question to ask you is this: How did C survive all these
years without such an obviously essential feature? How was
anybody able to construct programs of 100,000 plus lines of C
that worked well,without this feature? I'm a naive programmer;
there is some magic there that escapes me.
     BTW using pointers to the array doesn't help. We still
have to check the value of the offset.
     Thanks in advance for somebody's enlightened comment.
Malcolm Bersohn
[e-mail]