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From: amado.alves@gmail.com
Newsgroups: comp.lang.ada
Subject: Re: Opening a file vs. creating if not yet exists
Date: Tue, 19 Aug 2008 05:58:09 -0700 (PDT)
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> begin
>    Open (File, Append_File, "file.txt");
> exception
>    when Name_Error =>
>       Create (File, Append_File, "file.txt");
> end;
>
> Is the above idiomatic (ie. well understood and accepted as common
> practice)?

There seems to be two schools of though regarding the use of
exceptions for logic.
Some of us accept the idiom happily.
But probably the most conventional school is the "don't"
So in this particular case and if you are using Ada 2005 then you
might consider the uncontroversial

if Ada.Directories.File_Exists (Filename) then
   Open (...)
else
   Create (...)
end if;