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reply Igor <Vladamir.I google.com> writes:
Is there a GC-less array that we can use out of the box or do I 
have to create my own?
Jan 25 2016
next sibling parent reply maik klein <maikklein googlemail.com> writes:
On Tuesday, 26 January 2016 at 03:03:40 UTC, Igor wrote:

 Is there a GC-less array that we can use out of the box or do I 
 have to create my own?


https://dlang.org/phobos/std_container_array.html
Jan 25 2016
parent reply Igor <Vladamir.I google.com> writes:
On Tuesday, 26 January 2016 at 03:06:40 UTC, maik klein wrote:

 On Tuesday, 26 January 2016 at 03:03:40 UTC, Igor wrote:

 Is there a GC-less array that we can use out of the box or do 
 I have to create my own?


 https://dlang.org/phobos/std_container_array.html


How do we use std.algorithm with it? I could like to use find but 
I have no luck.

I have

std.container.array!MyClass classes;

then std.algorithm.find!("a.myInt == b")(classes, 3)

I was hoping this would find the first object in classes who has 
myInt == 3 but I just get many errors about not being able to 
find the right definition.

I guess std.container.array isn't a range? Or am I using it wrong?
Jan 25 2016
next sibling parent reply Adam D. Ruppe <destructionator gmail.com> writes:
On Tuesday, 26 January 2016 at 04:31:07 UTC, Igor wrote:

 then std.algorithm.find!("a.myInt == b")(classes, 3)


Try

std.algorithm.find!("a.myInt == b")(classes[], 3)

notice the [] after classes



 I guess std.container.array isn't a range? Or am I using it 
 wrong?


Containers aren't really ranges, they instead *offer* ranges that 
iterate over them. Built in arrays are a bit special in that they 
do this implicitly so the line is more blurred there, but it is a 
general rule that you need to get a range out of a container.

Otherwise, consider that iterating over it with popFront would 
result in the container being automatically emptied and not 
reusable!
Jan 25 2016
parent reply Igor <Vladamir.I google.com> writes:
On Tuesday, 26 January 2016 at 04:38:13 UTC, Adam D. Ruppe wrote:

 On Tuesday, 26 January 2016 at 04:31:07 UTC, Igor wrote:

 then std.algorithm.find!("a.myInt == b")(classes, 3)


 Try

 std.algorithm.find!("a.myInt == b")(classes[], 3)

 notice the [] after classes



 I guess std.container.array isn't a range? Or am I using it 
 wrong?


 Containers aren't really ranges, they instead *offer* ranges 
 that iterate over them. Built in arrays are a bit special in 
 that they do this implicitly so the line is more blurred there, 
 but it is a general rule that you need to get a range out of a 
 container.

 Otherwise, consider that iterating over it with popFront would 
 result in the container being automatically emptied and not 
 reusable!


Ok, does the [] do any conversion or any thing I don't want or 
does it just make the template know we are working over an array?

Are there any performance issues? I am already using a for loop 
to find the type, it's 6 lines of code. I was hoping to get that 
down to one or 2 and make it a bit easier to understand.

	App app = null;
	for(int i = 0; i < Apps.length(); i++)
		if ((Apps[i] !is null) && (Apps[i].hWnd == hWnd))
		{
			app = Apps[i];
			break;
		}

versus

find!("a.hWnd == b")(Apps[], hWnd);

Does [] take time to convert to a built in a array or range or 
whatever or will it be just as fast as the above code?
Jan 25 2016
parent Olivier Pisano <olivier.pisano supersonicimagine.com> writes:
On Tuesday, 26 January 2016 at 05:53:29 UTC, Igor wrote:

 On Tuesday, 26 January 2016 at 04:38:13 UTC, Adam D. Ruppe 
 wrote:

 On Tuesday, 26 January 2016 at 04:31:07 UTC, Igor wrote:

 then std.algorithm.find!("a.myInt == b")(classes, 3)


 Try

 std.algorithm.find!("a.myInt == b")(classes[], 3)

 notice the [] after classes



 I guess std.container.array isn't a range? Or am I using it 
 wrong?


 Containers aren't really ranges, they instead *offer* ranges 
 that iterate over them. Built in arrays are a bit special in 
 that they do this implicitly so the line is more blurred 
 there, but it is a general rule that you need to get a range 
 out of a container.

 Otherwise, consider that iterating over it with popFront would 
 result in the container being automatically emptied and not 
 reusable!


 Ok, does the [] do any conversion or any thing I don't want or 
 does it just make the template know we are working over an 
 array?

 Are there any performance issues? I am already using a for loop 
 to find the type, it's 6 lines of code. I was hoping to get 
 that down to one or 2 and make it a bit easier to understand.

 	App app = null;
 	for(int i = 0; i < Apps.length(); i++)
 		if ((Apps[i] !is null) && (Apps[i].hWnd == hWnd))
 		{
 			app = Apps[i];
 			break;
 		}

 versus

 find!("a.hWnd == b")(Apps[], hWnd);

 Does [] take time to convert to a built in a array or range or 
 whatever or will it be just as fast as the above code?


The [] operator returns a Range object iterating over the Array 
elements, similarly to what the begin()/end() cbegin()/cend() 
function pairs do in C++. The range object does not copy the 
array element, only contains a slice to them.
So your question ends up in comparing hand-written loops over 
std::find_if().
Jan 26 2016
prev sibling parent Kapps <opantm2+spam gmail.com> writes:
On Tuesday, 26 January 2016 at 04:31:07 UTC, Igor wrote:

 On Tuesday, 26 January 2016 at 03:06:40 UTC, maik klein wrote:

 On Tuesday, 26 January 2016 at 03:03:40 UTC, Igor wrote:

 Is there a GC-less array that we can use out of the box or do 
 I have to create my own?


 https://dlang.org/phobos/std_container_array.html


 How do we use std.algorithm with it? I could like to use find 
 but I have no luck.

 I have

 std.container.array!MyClass classes;

 then std.algorithm.find!("a.myInt == b")(classes, 3)

 I was hoping this would find the first object in classes who 
 has myInt == 3 but I just get many errors about not being able 
 to find the right definition.

 I guess std.container.array isn't a range? Or am I using it 
 wrong?


First, should be std.container.array.Array!MyClass. However I 
don't think(?) that the Array struct is a range itself, you might 
have to use classes[] instead to get a slice of the array.
Jan 25 2016
prev sibling next sibling parent Nemo <thisIsntMyEmailAddress gmail.com> writes:
On Tuesday, 26 January 2016 at 03:03:40 UTC, Igor wrote:

 Is there a GC-less array that we can use out of the box or do I 
 have to create my own?


There's one in emsi containers.
Jan 25 2016
prev sibling next sibling parent Jonathan M Davis via Digitalmars-d-learn writes:
On Tuesday, January 26, 2016 03:03:40 Igor via Digitalmars-d-learn wrote:

 Is there a GC-less array that we can use out of the box or do I
 have to create my own?


If what you want is a dynamic array (as opposed std.container.Array), then
you can simply malloc the memory and then slice it to get a dynamic array.
It's just that it's then up to you to manage the memory properly, and if you
attempt to append or concatenate, it'll result in the GC allocating a new
array.

- Jonathan M Davis
Jan 25 2016
prev sibling parent ZombineDev <valid_email he.re> writes:
On Tuesday, 26 January 2016 at 03:03:40 UTC, Igor wrote:

 Is there a GC-less array that we can use out of the box or do I 
 have to create my own?


If you want containers, use:
http://code.dlang.org/packages/emsi_containers

If you just need an array, use:
Jan 26 2016