newbie question: Can D do this?
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]; 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] 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. I find the 3 features above extremely convenient in every day coding. Thanks, -clk
Re: newbie question: Can D do this?
On 19.12.2011 17:17, clk wrote:
1) Does D support something like the javascript 1.8 destructuring
assigment (multiple assigment in python):
[a, b] = [b, a];
I don't think so, but you can do something like this with templates:
void swap(alias a, alias b)() {
auto t = a;
a = b;
b = t;
}
int a = 1, b = 2;
swap!(a, b);
assert(a == 2);
assert(b == 1);
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]
Don't think so. You can use std.algorithm, but it's a bit harder to read:
auto arr = [1,2,3,4,5,6];
auto res = array(pipe!(filter!"a>3", map!"a*2")(arr));
assert(res == [8,10,12]);
// or
auto res2 = array(map!"a*2"(filter!"a>3"(arr)));
assert(res2 == [8,10,12]);
But I'm a newbie myself.
Re: newbie question: Can D do this?
On Monday, December 19, 2011 11:17:43 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]; No. You'd have to use std.algorithm.swap. > 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, but you can do similar stuff with std.algorithm. auto transformed = map!func(filter!cond(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. Use std.range.stride. If you want a new array from it, then use std.array.array on the result. Otherwise, it's a range (see http://www.informit.com/articles/printerfriendly.aspx?p=1407357 for a general explanation of the concept of ranges) but not an array. e.g. auto arr = array(stride([1, 2, 3, 4, 5], 2)); - Jonathan M Davis
Re: newbie question: Can D do this?
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..$:2] would refer to [1, 3, 5], etc..., where 2 is the
> non unit stride. Or is the find function from std.algorithm the only
> option to achieve the same behavior.
std.range.stride does that:
import std.range;
// ...
stride([1, 2, 3, 4, 5], 2)
>
> I find the 3 features above extremely convenient in every day coding.
> Thanks,
> -clk
>
>
Ali
Re: newbie question: Can D do this?
On 12/19/2011 09:17 AM, clk wrote: Hello, I'm new to this mailing list. I'm trying to learn D to eventually use it in production code. I'm a little bit intimidated by the fact that the topics in the d-learn list look rather advanced to a newbie like me. I have 3 fairly simple questions: 1) Does D support something like the javascript 1.8 destructuring assigment (multiple assigment in python): [a, b] = [b, a]; I would love multiple assignment like this, but it's tricky. But your usage isn't really multiple assignment as much as it is a swap. What I'd love is something like this: [a, b, c] = [get_a(), get_b(), get_c()]; Or [a, b, c] = [to!(int)(argv[1]), some_other_value, argv[4]); 2) D doesn't seem to support the list comprehension syntax available in python and javascript. Is this correct? [f(x) for x in list if condition] No, D's syntax is very C-ish. I don't expect syntax like this to ever show up (though what you are doing is possible with things like std.algorithm) 3) D's slice operator apparently doesn't allow the use of a stride other than unity as is allowed with fortran and matlab. Is there a way to implement this feature so that [1, 2, 3, 4, 5][0..$: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
Re: newbie question: Can D do this?
On Mon, 19 Dec 2011 17:17:43 +0100, 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]; 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);
Re: newbie question: Can D do this?
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
Re: newbie question: Can D do this?
On Monday, December 19, 2011 11:07:49 Ali Çehreli 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
Re: newbie question: Can D do this?
On Monday, 19 December 2011 at 19:01:10 UTC, Simen Kjærås wrote: import std.typetuple : TypeTuple; import std.typecons : tuple; TypeTuple!(a, b) = tuple(b,a); There is a pull request implementing multiple variable declarations: https://github.com/D-Programming-Language/dmd/pull/341 However, the right hand side must still be a tuple.
Re: newbie question: Can D do this?
Thank you for your quick replies. I'm impressed by the helpfulness and
dedication of the D community!
Here's another one. Is there a way to pass arguments to functions by
keyword as in the calls to f and g below?
void f(int a = 0, int b = 1) {}
void g(int a) {}
void main() {
f(b = 1, a = 0); // compile error
g(a = 0); // also compile error
}
On 12/19/2011 03:00 PM, digitalmars-d-learn-requ...@puremagic.com wrote:
Send Digitalmars-d-learn mailing list submissions to
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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
To: digitalmars-d-learn@puremagic.com
Subject: Re: newbie question: Can D do this?
Message-ID:
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
To: digitalmars-d-learn@puremagic.com
Subject: Re: newbie question: Can D do this?
Message-ID:
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
Re: newbie question: Can D do this?
On 12/20/2011 03:18 PM, clk wrote:
Thank you for your quick replies. I'm impressed by the helpfulness and
dedication of the D community!
Here's another one. Is there a way to pass arguments to functions by
keyword as in the calls to f and g below?
void f(int a = 0, int b = 1) {}
void g(int a) {}
void main() {
f(b = 1, a = 0); // compile error
g(a = 0); // also compile error
}
No, there are no named arguments in D. Having them would sometimes be
useful, but the drawback is that the parameter names become part of the
public interface.
On 12/19/2011 03:00 PM, digitalmars-d-learn-requ...@puremagic.com wrote:
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
To:digitalmars-d-learn@puremagic.com
Subject: Re: newbie question: Can D do this?
Message-ID:
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
To:digitalmars-d-learn@puremagic.com
Subject: Re: newbie question: Can D do this?
Message-ID:
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.algorit
Re: newbie question: Can D do this?
On Tue, 20 Dec 2011 09:18:16 -0500, clk wrote:
Thank you for your quick replies. I'm impressed by the helpfulness and
dedication of the D community!
Here's another one. Is there a way to pass arguments to functions by
keyword as in the calls to f and g below?
void f(int a = 0, int b = 1) {}
void g(int a) {}
void main() {
f(b = 1, a = 0); // compile error
g(a = 0); // also compile error
}
No. There are workarounds, but they are quite ugly.
-Steve
Re: newbie question: Can D do this?
> On 20/12/2011 14:18, clk wrote:
>> Here's another one. Is there a way to pass arguments to functions by
>> keyword as in the
>> calls to f and g below?
I remember a discussion about year ago or so.
It seems doable to have some kind of function transformer (adaptor?) for this.
from:
int foo(int a = 0, int b = 1, double c = 0.0, bool d = false) { return 1;}
alias namedParams!foo nfoo; // transform it into a called-by-name function.
nfoo(["d": true]); // a = 0, b = 1, c = 0.0, d = true
nfoo(["d" : true], ["b" : 100]); // a=0, b=100, c=0.0, d=true
nfoo(1, 2, ["d" : true]); // a=1, b=2, c=0.0, d=true
That is, it expects some values, then string/values couples as
associative arrays.
Would that be palatable? Because I think it's doable.
To obtain the arguments names:
int foo(int a, int b, double c = 0.0, bool d = true) { return 1;}
template Name(alias foo) if (isCallable!foo)
{
enum string Name = S!(foo.stringof);
}
template S(string s) // this template is just a trick because
foo.stringof directly displeases DMD
{
enum string S = s;
}
writeln(Name!foo); // "int(int a, int b, double c = 0, bool d = true)"
So this gives us:
- the arguments names
- which ones have default values
- what is that default value
The difficulty here is correctly parsing the ( ,,,) part, without
getting desoriented by argument types that themselves use (,), like
templated types.
I think that would make for an small & interesting community challenge.
Philippe
Re: newbie question: Can D do this?
On Mon, Dec 19, 2011 at 17:17, clk wrote:
> 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]
Correct. As other have said, it's doable by combining std functions.
As fas as I know, we do not have a cartesian product range, to iterate
on all combinations of two or more ranges.
[f(x,y) for x in list1 for y in list2 if condition]
I gave it a try a few years ago and could get something like this:
auto lc = comp!("tuple(a,b,c)", "a*a+b*b == c*c && a mapper, condition,
input ranges, as many as you wish
But at the time I couldn't find a way to do bindings, that is:
[f(x,y) for x in [0..10] for y in [0..x]]
-> the range iterated by y depends on x.
If anyone has an idea, I'm game.
Philippe
Re: newbie question: Can D do this?
On 20/12/2011 20:36, Philippe Sigaud wrote: That is, it expects some values, then string/values couples as associative arrays. I've a recollection of seeing something like this in the PHP library, but I forget where. I believe it's used in some functions that have a lot of options to set, such that you'll typically just want to set a few of them in a given call. Stewart.
Re: newbie question: Can D do this?
In PHP frameworks often use $option arrays which are some kind of key
value pairs. they are merged with the default valuzes inside the function.
pro:
- you can pass an argument by name
- you only need to pass those who needed.
cons:
- hash arrays
it should be possible to create a similar method in d. but I really
don't like this solution in d. it feels bad and looks ugly.
query(array(
'firstname' => 'John',
'country' => 'France',
'order' => 'asc'
));
class Model
{
function query($options = array())
{
// merge with defaults
$options = array_merge(array(
'deep' => true,
'order' => 'desc',
'type' => 'sql',
'backend' => 'mysql'
...
), $options);
}
}
?>
Re: newbie question: Can D do this?
Timon Gehr , dans le message (digitalmars.D.learn:31142), a écrit :
> On 12/20/2011 03:18 PM, clk wrote:
>> Thank you for your quick replies. I'm impressed by the helpfulness and
>> dedication of the D community!
>> Here's another one. Is there a way to pass arguments to functions by
>> keyword as in the calls to f and g below?
>>
>> void f(int a = 0, int b = 1) {}
>> void g(int a) {}
>>
>> void main() {
>> f(b = 1, a = 0); // compile error
>> g(a = 0); // also compile error
>> }
>>
>>
>
> No, there are no named arguments in D. Having them would sometimes be
> useful,
> but the drawback is that the parameter names become part of the
> public interface.
Well, that's precisely the point. And it is a drawback if parameters are
systematically names, but not if it is triggered only on demand.
Example :
void foo(int a, int b:, int c:);
void main() {
foo(1, 2, 3);
foo(1, c: 3, b: 2;
foo(a: 1, b: 2, c: 3); // error : a is not a named parameter.
}
In the example, ":" is used to make a named parameter to recall the use
when you call the function.
Re: newbie question: Can D do this?
Philippe,
Thank you very much for your response. It looks similar to what I've
done in javascript by wrapping all function arguments into a single
object literal but the D alternative you propose is a little to
convoluted for a beginner like me. Perhaps I'll understand it better
after I'm done reading the D book.
To bad D doesn't support passing arguments by name. It makes code so
much easier to read, especially in large projects. Even Fortran allows it.
-clk
(Christian Keppenne)
On 20/12/2011 14:18, clk wrote:
I remember a discussion about year ago or so.
It seems doable to have some kind of function transformer (adaptor?) for this.
from:
int foo(int a = 0, int b = 1, double c = 0.0, bool d = false) { return 1;}
alias namedParams!foo nfoo; // transform it into a called-by-name function.
nfoo(["d": true]); // a = 0, b = 1, c = 0.0, d = true
nfoo(["d" : true], ["b" : 100]); // a=0, b=100, c=0.0, d=true
nfoo(1, 2, ["d" : true]); // a=1, b=2, c=0.0, d=true
That is, it expects some values, then string/values couples as
associative arrays.
Would that be palatable? Because I think it's doable.
To obtain the arguments names:
int foo(int a, int b, double c = 0.0, bool d = true) { return 1;}
template Name(alias foo) if (isCallable!foo)
{
enum string Name = S!(foo.stringof);
}
template S(string s) // this template is just a trick because
foo.stringof directly displeases DMD
{
enum string S = s;
}
writeln(Name!foo); // "int(int a, int b, double c = 0, bool d = true)"
So this gives us:
- the arguments names
- which ones have default values
- what is that default value
The difficulty here is correctly parsing the ( ,,,) part, without
getting desoriented by argument types that themselves use (,), like
templated types.
I think that would make for an small& interesting community challenge.
Philippe
End of Digitalmars-d-learn Digest, Vol 71, Issue 34
***
Re: newbie question: can D do this?
Philippe,
I don't understand the example below to simulate the list comprehension
syntax. Are input1, input2 and input3 ranges? Where is the comp
function defined?
Thank you,
-clk
(Christian Keppenne)
auto lc = comp!("tuple(a,b,c)", "a*a+b*b == c*c&& a
--
Message: 2
Date: Tue, 20 Dec 2011 21:45:26 +0100
From: Philippe Sigaud
To: "digitalmars.D.learn"
Subject: Re: newbie question: Can D do this?
Message-ID:
Content-Type: text/plain; charset=UTF-8
On Mon, Dec 19, 2011 at 17:17, clk wrote:
Correct. As other have said, it's doable by combining std functions.
As fas as I know, we do not have a cartesian product range, to iterate
on all combinations of two or more ranges.
[f(x,y) for x in list1 for y in list2 if condition]
I gave it a try a few years ago and could get something like this:
auto lc = comp!("tuple(a,b,c)", "a*a+b*b == c*c&& amapper, condition,
input ranges, as many as you wish
But at the time I couldn't find a way to do bindings, that is:
[f(x,y) for x in [0..10] for y in [0..x]]
-> the range iterated by y depends on x.
If anyone has an idea, I'm game.
Philippe
Re: newbie question: Can D do this?
On Thu, Dec 22, 2011 at 16:37, clk wrote: > Philippe, > Thank you very much for your response. It looks similar to what I've done > in javascript by wrapping all function arguments into a single object > literal but the D alternative you propose is a little to convoluted for a > beginner like me. Perhaps I'll understand it better after I'm done reading > the D book. Oh yes, it *is* convoluted :) What I was proposing is to try and code it myself, if others find the resulting syntax acceptable. I wouldn't know, since I do not use named arguments myself.
Re: newbie question: can D do this?
On Thu, Dec 22, 2011 at 16:45, clk wrote: > Philippe, > I don't understand the example below to simulate the list comprehension > syntax. Are input1, input2 and input3 ranges? Yes, inputs are ranges. Sorry, I was perhaps a bit hasty in answering. The code is on github: https://github.com/PhilippeSigaud/dranges comp() is defined into the algorithm.d module. Github does not host the docs, but I generated them on dsource a long time ago: http://svn.dsource.org/projects/dranges/trunk/dranges/docs/algorithm.html (search for comp, there is no anchor. I think there wasn't a way to make them easily on DDoc a year ago)
