Send Digitalmars-d-learn mailing list submissions to
digitalmars-d-learn@puremagic.com
To subscribe or unsubscribe via the World Wide Web, visit
http://lists.puremagic.com/cgi-bin/mailman/listinfo/digitalmars-d-learn
or, via email, send a message with subject or body 'help' to
digitalmars-d-learn-requ...@puremagic.com
You can reach the person managing the list at
digitalmars-d-learn-ow...@puremagic.com
When replying, please edit your Subject line so it is more specific
than "Re: Contents of Digitalmars-d-learn digest..."
Today's Topics:
1. Re: newbie question: Can D do this? (Ali ?ehreli)
2. Re: newbie question: Can D do this? (Kai Meyer)
3. Re: newbie question: Can D do this? (Simen Kj?r?s)
4. Re: newbie question: Can D do this? (Ali ?ehreli)
5. Re: newbie question: Can D do this? (Jonathan M Davis)
----------------------------------------------------------------------
Message: 1
Date: Mon, 19 Dec 2011 10:41:29 -0800
From: Ali ?ehreli<acehr...@yahoo.com>
To: digitalmars-d-learn@puremagic.com
Subject: Re: newbie question: Can D do this?
Message-ID:<jco0gq$1ilt$1...@digitalmars.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
On 12/19/2011 08:17 AM, clk wrote:
> I'm a little bit intimidated by the fact that the topics in the d-learn
> list look rather advanced to a newbie like me.
We need more newbie topics here! :)
> 1) Does D support something like the javascript 1.8 destructuring
> assigment (multiple assigment in python):
>
> [a, b] = [b, a];
No multiple assignment like that. But useful approarches exist for most
needs, like the swap that simendsjo has shown.
> 2) D doesn't seem to support the list comprehension syntax available in
> python and javascript. Is this correct?
>
> [f(x) for x in list if condition]
List comprehension is not part of the language.
import std.algorithm;
void f(int x)
{}
bool condition(int x)
{
return true;
}
void main()
{
auto list = [ 0, 1, 2 ];
map!f(filter!condition(list));
}
You can define f and condition within the body of main().
It is possible to use function literals as well:
import std.algorithm;
void main()
{
auto list = [ 0, 1, 2 ];
map!((x){
/* ... this is f(x) ...*/
})(filter!((x) {
return true; /* ... condition ... */
})(list));
}
> 3) D's slice operator apparently doesn't allow the use of a stride other
> than unity as is allowed with fortran and matlab. Is there a way to
> implement this feature so that
>
> [1, 2, 3, 4, 5][0..$:2] would refer to [1, 3, 5], etc..., where 2 is the
> non unit stride. Or is the find function from std.algorithm the only
> option to achieve the same behavior.
std.range.stride does that:
import std.range;
// ...
stride([1, 2, 3, 4, 5], 2)
>
> I find the 3 features above extremely convenient in every day coding.
> Thanks,
> -clk
>
>
Ali
------------------------------
Message: 2
Date: Mon, 19 Dec 2011 11:50:33 -0700
From: Kai Meyer<k...@unixlords.com>
To: digitalmars-d-learn@puremagic.com
Subject: Re: newbie question: Can D do this?
Message-ID:<jco11q$1lle$1...@digitalmars.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
On 12/19/2011 09:17 AM, clk wrote:
Hello,
I'm new to this mailing list. I'm trying to learn D to eventually use it
in production code.
I'm a little bit intimidated by the fact that the topics in the d-learn
list look rather advanced to a newbie like me.
I have 3 fairly simple questions:
1) Does D support something like the javascript 1.8 destructuring
assigment (multiple assigment in python):
[a, b] = [b, a];
I would love multiple assignment like this, but it's tricky. But your
usage isn't really multiple assignment as much as it is a swap. What I'd
love is something like this:
[a, b, c] = [get_a(), get_b(), get_c()];
Or
[a, b, c] = [to!(int)(argv[1]), some_other_value, argv[4]);
2) D doesn't seem to support the list comprehension syntax available in
python and javascript. Is this correct?
[f(x) for x in list if condition]
No, D's syntax is very C-ish. I don't expect syntax like this to ever
show up (though what you are doing is possible with things like
std.algorithm)
3) D's slice operator apparently doesn't allow the use of a stride other
than unity as is allowed with fortran and matlab. Is there a way to
implement this feature so that
[1, 2, 3, 4, 5][0..$:2] would refer to [1, 3, 5], etc..., where 2 is the
non unit stride. Or is the find function from std.algorithm the only
option to achieve the same behavior.
Ya, std.range, like Ali said.
I find the 3 features above extremely convenient in every day coding.
Thanks,
-clk
------------------------------
Message: 3
Date: Mon, 19 Dec 2011 20:01:06 +0100
From: Simen Kj?r?s<simen.kja...@gmail.com>
To: digitalmars-d-learn@puremagic.com
Subject: Re: newbie question: Can D do this?
Message-ID:<op.v6q234mt0gp...@biotronic.lan>
Content-Type: text/plain; charset=utf-8; format=flowed; delsp=yes
On Mon, 19 Dec 2011 17:17:43 +0100, clk<c...@clksoft.com> wrote:
Hello,
I'm new to this mailing list. I'm trying to learn D to eventually use
it in production code.
I'm a little bit intimidated by the fact that the topics in the d-learn
list look rather advanced to a newbie like me.
I have 3 fairly simple questions:
1) Does D support something like the javascript 1.8 destructuring
assigment (multiple assigment in python):
[a, b] = [b, a];
This, or something quite like it, was covered on Saturday in the thread
"Alias/Ref Tuples ?". This works (but is hardly as elegant as Python's
syntax:
import std.typetuple : TypeTuple;
import std.typecons : tuple;
TypeTuple!(a, b) = tuple(b,a);
------------------------------
Message: 4
Date: Mon, 19 Dec 2011 11:07:49 -0800
From: Ali ?ehreli<acehr...@yahoo.com>
To: digitalmars-d-learn@puremagic.com
Subject: Re: newbie question: Can D do this?
Message-ID:<jco225$1r5m$1...@digitalmars.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
On 12/19/2011 10:39 AM, Jonathan M Davis wrote:
> it's a range (see
> http://www.informit.com/articles/printerfriendly.aspx?p=1407357 for a
general
> explanation of the concept of ranges)
That's a great article.[1] I hope that this chapter is more
beginner-friendly:
http://ddili.org/ders/d.en/ranges.html
Ali
[1] Andrei's article has a Turkish translation as well:
http://ddili.org/makale/eleman_erisimi_uzerine.html
------------------------------
Message: 5
Date: Mon, 19 Dec 2011 14:30:39 -0500
From: "Jonathan M Davis"<jmdavisp...@gmx.com>
To: "digitalmars.D.learn"<digitalmars-d-learn@puremagic.com>
Subject: Re: newbie question: Can D do this?
Message-ID:<20111219193039.5...@gmx.com>
Content-Type: text/plain; charset="utf-8"
On Monday, December 19, 2011 11:07:49 Ali ?ehreli wrote:
That's a great article.[1] I hope that this chapter is more
beginner-friendly:
http://ddili.org/ders/d.en/ranges.html
Cool. One of the things that we're missing on the website is a solid article
on ranges (I started such an article a while back and really should go back
and finish it), but having something like this to link to should be quite
useful. I'll have to give it a read. Thanks!
- Jonathan M Davis
------------------------------
_______________________________________________
Digitalmars-d-learn mailing list
Digitalmars-d-learn@puremagic.com
http://lists.puremagic.com/cgi-bin/mailman/listinfo/digitalmars-d-learn
End of Digitalmars-d-learn Digest, Vol 71, Issue 29
***************************************************
