Re: Lack of formal syntax undermines Ada

[Robert A Duff <bobduff@shell01.TheWorld.com>]

John McCabe <john@nospam.assen.demon.co.uk.nospam> writes:

> Robert A Duff <bobduff@shell01.TheWorld.com> wrote:
>
>>John McCabe <john@nospam.assen.demon.co.uk.nospam> writes:
>>
>>> As I understand it, that was deliberate; Ada's feature that functions
>>> may not have side-effects ...
>>
>>Ada functions can have side effects.
>
> Bugger - where did I get that idea from then (have to admit, it's been
> a while since I paid a lot of attention to Ada!)

Perhaps from the fact that 'in out' and 'out' parameters are illegal for
functions.  As Robert Dewar likes to point out, the effect of this rule
is that functions can have side effects, so long as they are not
properly documented.  ;-)

Functions can modify global variables if they are visible.
Functions can also modify data via pointers.

- Bob