Re: Specifying eponymous template "internal parameter"
On Tue, Jan 8, 2013 at 9:53 PM, Era Scarecrow wrote: > On Tuesday, 8 January 2013 at 20:48:24 UTC, Philippe Sigaud wrote: > > On Tue, Jan 8, 2013 at 8:39 PM, monarch_dodra wrote: >> > > Anyways, the details are there if you want details. I don't know which >>> way it'll go. >>> >> >> OK. I'll wait for a stabilized syntax for alias this. >> >> But the new `alias newSym = oldSym;` is implemented, right? >> > > As far as I can tell, Yes. I'll still be using 'alias oldSym newSym;' for > a long time most likely, unless there's a big reason to switch. > When I stop D for a few weeks and come back to it, I'm sometimes confused as to which is the old symbol and which is the new one. For a declaration: type newSym = oldSym; is standard. alias nemSym = oldSym; will be easy to get used to
Re: Specifying eponymous template "internal parameter"
On Tuesday, 8 January 2013 at 20:48:24 UTC, Philippe Sigaud wrote: On Tue, Jan 8, 2013 at 8:39 PM, monarch_dodra wrote: Anyways, the details are there if you want details. I don't know which way it'll go. OK. I'll wait for a stabilized syntax for alias this. But the new `alias newSym = oldSym;` is implemented, right? Definitely.
Re: Specifying eponymous template "internal parameter"
On Tuesday, 8 January 2013 at 20:48:24 UTC, Philippe Sigaud wrote: On Tue, Jan 8, 2013 at 8:39 PM, monarch_dodra wrote: Anyways, the details are there if you want details. I don't know which way it'll go. OK. I'll wait for a stabilized syntax for alias this. But the new `alias newSym = oldSym;` is implemented, right? As far as I can tell, Yes. I'll still be using 'alias oldSym newSym;' for a long time most likely, unless there's a big reason to switch.
Re: Specifying eponymous template "internal parameter"
On Tue, Jan 8, 2013 at 8:39 PM, monarch_dodra wrote: > > Anyways, the details are there if you want details. I don't know which way > it'll go. > OK. I'll wait for a stabilized syntax for alias this. But the new `alias newSym = oldSym;` is implemented, right?
Re: Specifying eponymous template "internal parameter"
On Tuesday, 8 January 2013 at 18:40:55 UTC, Philippe Sigaud wrote: On Tue, Jan 8, 2013 at 5:59 PM, monarch_dodra It works for everything except "alias something this". Not that it can't be done, but there were discussions for another syntax specific to alias this. The grammar says: *AliasThisDeclaration*: *alias* *Identifier* *this* *alias* *this* *=* * Identifier* AliasThisDeclaration: alias Identifier this alias this = Identifier Nice nice nice. Ah: There it is: https://github.com/D-Programming-Language/dmd/pull/1413 The plan was to kill it before it made it into 2.061, but I guess it made it. Anyways, the details are there if you want details. I don't know which way it'll go.
Re: Specifying eponymous template "internal parameter"
On Tuesday, 8 January 2013 at 16:56:05 UTC, Philippe Sigaud wrote:
On Tue, Jan 8, 2013 at 10:58 AM, Simen Kjaeraas
wrote:
alias fun2 = fun!("++a", "--a");
Wait wait wait.
Since when is this a valid alias syntax?
Is that another Easter egg hidden in 2.061?
Oh. New alias syntax. Nice ain't it?
It works for everything except "alias something this". Not that
it can't be done, but there were discussions for another syntax
specific to alias this.
Re: Specifying eponymous template "internal parameter"
On Tue, Jan 8, 2013 at 10:58 AM, Simen Kjaeraas wrote:
>alias fun2 = fun!("++a", "--a");
>
Wait wait wait.
Since when is this a valid alias syntax?
Is that another Easter egg hidden in 2.061?
Re: Specifying eponymous template "internal parameter"
On Tuesday, 8 January 2013 at 11:09:58 UTC, Simen Kjaeraas wrote:
On 2013-16-08 11:01, monarch_dodra
wrote:
On Tuesday, 8 January 2013 at 09:59:26 UTC, Simen Kjaeraas
wrote:
alias fun2 = fun!("++a", "--a");
auto m = fun2!(ubyte)(1);
Nice!
And now, for the 1M$ question: Can I rely on this behavior, or
is this an accepts invalid...?
You can rely on it.
Thank you.
Re: Specifying eponymous template "internal parameter"
On 2013-16-08 11:01, monarch_dodra wrote:
On Tuesday, 8 January 2013 at 09:59:26 UTC, Simen Kjaeraas wrote:
alias fun2 = fun!("++a", "--a");
auto m = fun2!(ubyte)(1);
Nice!
And now, for the 1M$ question: Can I rely on this behavior, or is this
an accepts invalid...?
You can rely on it.
--
Simen
Re: Specifying eponymous template "internal parameter"
On Tuesday, 8 January 2013 at 09:59:26 UTC, Simen Kjaeraas wrote:
On 2013-55-08 09:01, monarch_dodra
wrote:
Sometimes (especially in phobos), one defines a parametrized
template, that resolves to a templated function.
This is a nifty trick, because it allows specifying a vararg
before the current type parameter, eg:
//
auto r = [1, 2, 3];
auto m = map!("++a", "--a")(r);
//
As you can see, the template guessed the type of r, even
though we used a vararg. This would not have worked with a
single template function.
My question though: I have a similar use case, but I NEED to
be able to explicitly specify the type of r: as such:
//
auto m = fun!("++a", "--a", ubyte)(1);
auto m = fun!("++a", "--a")!(ubyte)(1);
auto m = fun!("++a", "--a").fun!ubyte(1);
//
None of them work. In this specific case, I *need* to specify
that 1 is of type ubyte, but I really can't do it :/
Simplified example: in my use case, it is a
"immutable(int[])": Failure to specify the type means the
compiler strips tail immutability...
The only workaround I can find to make such a thing, is to
*not* use eponymous temples, and explicitly call an inner
function. This is ugly as sin, and it makes specifying the
internal parameter mandatory.
Any thoughts?
A non-eponymous template is currently the only way to do this.
Strangely, this works:
alias fun2 = fun!("++a", "--a");
auto m = fun2!(ubyte)(1);
Nice!
And now, for the 1M$ question: Can I rely on this behavior, or is
this an accepts invalid...?
Re: Specifying eponymous template "internal parameter"
On 2013-55-08 09:01, monarch_dodra wrote:
Sometimes (especially in phobos), one defines a parametrized template,
that resolves to a templated function.
This is a nifty trick, because it allows specifying a vararg before the
current type parameter, eg:
//
auto r = [1, 2, 3];
auto m = map!("++a", "--a")(r);
//
As you can see, the template guessed the type of r, even though we used
a vararg. This would not have worked with a single template function.
My question though: I have a similar use case, but I NEED to be able to
explicitly specify the type of r: as such:
//
auto m = fun!("++a", "--a", ubyte)(1);
auto m = fun!("++a", "--a")!(ubyte)(1);
auto m = fun!("++a", "--a").fun!ubyte(1);
//
None of them work. In this specific case, I *need* to specify that 1 is
of type ubyte, but I really can't do it :/
Simplified example: in my use case, it is a "immutable(int[])": Failure
to specify the type means the compiler strips tail immutability...
The only workaround I can find to make such a thing, is to *not* use
eponymous temples, and explicitly call an inner function. This is ugly
as sin, and it makes specifying the internal parameter mandatory.
Any thoughts?
A non-eponymous template is currently the only way to do this. Strangely,
this works:
alias fun2 = fun!("++a", "--a");
auto m = fun2!(ubyte)(1);
--
Simen
