Re: [Plib-devel] C++ Philosophy Question

[Steve B. <sjb...@ai...>]

Bill Weiland wrote:

> references are more precise/less error prone than pointers
> when e.g. a function arg. or member cannot/should not be
> NULL (and cannot/should not be changed dynamically)...

The thing I *really* dislike about ref parameters is that it's
possible to see this in the header for a library somewhere:

   void some_funtion ( int x ) ;

...you go and write code to use 'some_function' *knowing* for
sure that:

   x = 6 ;
   some_function ( x ) ;

*CANNOT* change the value of 'x'.

What's nasty about 'ref' arguments is that some subsequent
version of that library can change the parameter of
'some_function' to be 'ref' and then change the value of x
inside the function without the author of the application
code being aware that the libraries' policy has changed.
The old call to some_function still compiles!  Eeeekkkkk!

Also, I like to be able to look at some complex code
that uses 'some_function' and *know* that the parameter
isn't altered by the the function just by looking at the
call.  I don't even have to go off and read the manual
for 'some_function' in order to know that.

The nice thing about good old fashioned C-style pointers
is that when you see:


   x = 6 ;
   some_function ( & x ) ;

...that '&' shouts loudly to you to bear in mind that x may
well have been changed by the call.  If you don't see an '&'
then you don't need to know much about some_function in order
to see that it doesn't change 'x'.

That makes code MUCH more readable.

I think 'ref' is *EVIL* because its syntax doesn't make it
obvious.

> Anyway, that's it for religion, time to write some code.

Indeed.

-- 
Steve Baker                  http://web2.airmail.net/sjbaker1
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