Re: some questions re. Ada/GNAT from a C++/GCC user

[kcline@sun132.spd.dsccc.com (Kevin Cline)]

In article <Dp75DK.DMG@world.std.com>,
Robert A Duff <bobduff@world.std.com> wrote:
>Well, I'm not sure exactly what you're asking.  To print stuff out, you
>need some procedure that prints text strings, and you need some way to
>convert whatever you want to print out into a text string.  In Ada,
>'Image is used to convert simple data types like Integer and Float into
>human-readable Strings.  For complicated data types, you write your own
>Image function.  

This is a flaw in the Ada language design, IMHO.  Why should
different methods be used to externalize primitive and user-defined types?
It certainly makes program maintainence more difficult; imagine a change
from

	type sequence_number_type is 0..2**32-1

to

	type sequence_number_type is 
	record
	  time: time_type;
	  serial: 2**32-1;
	end;

If this change was not anticipated then every use of 'IMAGE to
output a sequence number must be changed to IMAGE().

>The "&" operator just concatenates Strings.  So to
>print out some stuff, you write:
>
>    Put("X = " & Integer'Image(X) & "; and List = " & Image(List));
>

Sloshing all those characters around unnecessarily gets a bit
expensive after a while.  This expression is likely to copy the list
image twice before it is actually output.
-- 
Kevin Cline