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From: "Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: if-then-no-else Programming
Date: Wed, 20 Apr 2016 16:07:24 -0700
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Date: 2016-04-20T16:07:24-07:00
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On 04/20/2016 12:56 AM, Charles H. Sampson wrote:
>
> Don't hold me to this, but I have this vague memory that somewhere back
> at the beginning of Ada there was a proposal that every if-statement had
> to have an else-statement. I don't remember if it was one of the early
> incarnations of Ada, somebody's proposed coding style, on one of the
> non-green language proposals.
>
> The point was to indicate in the code that the possibility of the
> if-condition's being false had been considered.

I don't require it for a simple if statement, but I use the rule that an if with 
an elsif must have an else. This shows that all alternatives have been 
considered. If the else part is null, it provides a convenient place for the 
comment explaining why no action is needed.

-- 
Jeff Carter
"[M]any were collected near them, ... to
enjoy the sight of a dead young lady, nay,
two dead young ladies, for it proved twice
as fine as the first report."
Persuasion
155