Re: Suggestion for Ada 200x - Interface inheritance

[Wesley Groleau <wesgroleau@despammed.com>]

>> Yeah. Pre- and post-conditions are easier, I guess, because they can't
>> break current code, while the introduction of 'throws' ('raises'?),
>> without some trick, would.

Indeed.  I was asked to fix an out of bounds exception
in Java once.  Chased an empty string down through several
layers of the call stack till I found that the class
that was supposed to get the string out of a database caught
file not found by creating an empty database, and handled
no such key in the database by returning an empty string.
For reasons which would take up unnecessary bandwidth,
the right thing to do was throw an exception instead of
pretending everything is OK for a later crash.  But that
meant adding a throws clause to each of hundreds of
files.