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From: "G.B." <bauhaus@futureapps.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Running a preprocessor from GPS?
Date: Tue, 28 Jul 2015 16:57:08 +0200
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Xref: news.eternal-september.org comp.lang.ada:27090
Date: 2015-07-28T16:57:08+02:00
List-Id: <comp.lang.ada>

On 28.07.15 15:49, EGarrulo wrote:

> In this case, a deficiency of Ada is that Ada doesn't allow you to
> evaluate an expression lazily.  Let's imagine that Ada had a `lazy`
> keyword to evaluate an expression lazily.  Then I could have written:
>
>      Trace (Me, lazy "Performing Step " & Step(...));
>
> without any need for a preprocessor.

A poor man's solution could establish a Boolean context
and then (i.e., after declaring DBG : Boolean)

   DBG := Trace(Me) and then Log("performing Step " & Step(42));


(where the Log function, if called, has the side effect of
printing its parameter.)