From: "Randy Brukardt" <randy@rrsoftware.com>
Subject: Re: Possible to recover default value of scalar type?
Date: Wed, 16 Dec 2020 18:45:17 -0600 [thread overview]
Message-ID: <rre9mu$sm7$1@franka.jacob-sparre.dk> (raw)
In-Reply-To: i3re1oF5omrU1@mid.individual.net
"Niklas Holsti" <niklas.holsti@tidorum.invalid> wrote in message
news:i3re1oF5omrU1@mid.individual.net...
> On 2020-12-15 3:27, Randy Brukardt wrote:
>> "AdaMagica" <christ-usch.grein@t-online.de> wrote in message
>> news:570e9d30-0b33-45f0-a9fe-163cc810a770n@googlegroups.com...
>>> Dmitry A. Kazakov schrieb am Montag, 14. Dezember 2020 um 10:38:42
>>> UTC+1:
>>>> procedure Library_Foo (Bar : Baz := Baz'Default_Value)
>>> Suppose type Baz has no default value aspect. Then a call Library_Foo
>>> without parameter would use what?
>>> A solution could be that the attribute is illegal if there is no aspect.
>>> The compiler knows.
>>
>> Not always. Never forget generics. One would hope to be able to use this
>> on
>> generic formal types, as most of them are going to have default values
>> (at
>> least in new code).
>
>
> The generic formal type declarations could be extended to indicate that a
> Default_Value is required, for example:
>
> generic
> type T is private with Default_Value;
Sure, but more complication. We (as a group) decided it wasn't worth it. I'd
rather extend <> anyway, and that would be allowed anywhere, much like a
raise_expression.
Randy.
next prev parent reply other threads:[~2020-12-17 0:45 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-13 9:54 Possible to recover default value of scalar type? reinert
2020-12-14 0:08 ` Stephen Leake
2020-12-14 6:09 ` reinert
2020-12-14 9:01 ` AdaMagica
2020-12-14 9:38 ` Dmitry A. Kazakov
2020-12-14 15:56 ` AdaMagica
2020-12-14 16:31 ` Dmitry A. Kazakov
2020-12-14 18:24 ` Simon Wright
2020-12-14 18:53 ` Dmitry A. Kazakov
2020-12-15 6:47 ` J-P. Rosen
2020-12-15 7:23 ` Dmitry A. Kazakov
2020-12-15 9:07 ` J-P. Rosen
2020-12-15 16:53 ` Simon Wright
2020-12-15 18:14 ` AdaMagica
2020-12-17 0:53 ` Randy Brukardt
2020-12-17 0:48 ` Randy Brukardt
2020-12-15 1:27 ` Randy Brukardt
2020-12-15 9:30 ` Niklas Holsti
2020-12-17 0:45 ` Randy Brukardt [this message]
2020-12-15 1:26 ` Randy Brukardt
2020-12-15 7:35 ` Dmitry A. Kazakov
2020-12-17 0:43 ` Randy Brukardt
2020-12-15 1:21 ` Randy Brukardt
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