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Date: Thu, 1 Mar 2018 15:47:17 -0800 (PST)
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Subject: Re: two questions on allocators
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Xref: reader02.eternal-september.org comp.lang.ada:50780
Date: 2018-03-01T15:47:17-08:00
List-Id: <comp.lang.ada>

On Thursday, March 1, 2018 at 4:17:55 PM UTC-7, Robert A Duff wrote:
> 
> I can't think of any case in which "not null" is better
> than the predicate.  Sometimes they are the same, sometimes
> "not null" is worse; hence my recommendation to not use it.

What about interfacing for a library: using "not null" on a parameter means that the body of the program needn't make the manual check for the parameter being null.

Probably with thin-bindings (ie if you're importing rather than exporting) is a good idea, too... then the Ada-side calls can catch it and save you from that madness.