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digitalmars.D.learn - Structure of Arrays vs Array of Structures

reply Per =?UTF-8?B?Tm9yZGzDtnc=?= <per.nordlow gmail.com> writes:
https://forum.dlang.org/post/cvsajblducyanpqahrwe forum.dlang.org

On Monday, 15 May 2017 at 06:44:53 UTC, Nordlöw wrote:

 After having watched Jonathan Blow's talk on Jai

 https://www.youtube.com/watch?v=TH9VCN6UkyQ&t=2880s

 I realized that we should add his Array-of-Structures (AoS) 
 concept to Phobos, preferrably in std.typecons.StructArrays, as 
 something like

 template StructArrays(Members...)


I have made some significant optimizations with regards to 
compilation performance at

https://github.com/nordlow/phobos-next/blob/master/src/soa.d
Aug 26 2019
parent reply Per =?UTF-8?B?Tm9yZGzDtnc=?= <per.nordlow gmail.com> writes:
On Monday, 26 August 2019 at 09:54:30 UTC, Per Nordlöw wrote:

 I have made some significant optimizations with regards to 
 compilation performance at

 https://github.com/nordlow/phobos-next/blob/master/src/soa.d


What is the preferred way to implement to support foreach over 
`x` in

     struct S { int i; float f; }
     auto x = SOA!S();
     foreach (S; x[])
     {
     }

?

Implement `opSlice` that returns a SOA.Range type?
Aug 26 2019
parent a11e99z <black80 bk.ru> writes:
On Monday, 26 August 2019 at 09:58:30 UTC, Per Nordlöw wrote:

 On Monday, 26 August 2019 at 09:54:30 UTC, Per Nordlöw wrote:

 I have made some significant optimizations with regards to 
 compilation performance at

 https://github.com/nordlow/phobos-next/blob/master/src/soa.d


 What is the preferred way to implement to support foreach over 
 `x` in

     struct S { int i; float f; }
     auto x = SOA!S();
     foreach (S; x[])
     {
     }

 ?

 Implement `opSlice` that returns a SOA.Range type?


1) not sure about opSlice cuz user can allocate every time when 
he need S[..] from SOA.
   easy call for user but its too expensive op.
   maybe better to define global array( T )( SOA!T {opt: int beg, 
int end}) that returns array.

 x.array or array( x ) or x.array( 10, 20)


   looks like DRT that means "some range to newly allocated 
array". and SOA to S is some calculated range - need construct 
each element.

2) x.items returns SOA.Range
Aug 26 2019