• James Lu (3/3) Sep 05 2019 Add GC-free closures to D. Less GC reliance means less memory
• James Lu (3/6) Sep 05 2019 The first question should be, does the current closure semantics
• Kagamin (3/5) Sep 08 2019 AFAIK, closure is allocated with _d_allocatememory hook. If you
• a11e99z (7/22) Sep 05 2019 2) lambda can capture something that stored in GC
• a11e99z (3/9) Sep 05 2019 more complicated visually and thoughtful but machine code

James Lu <jamtlu gmail.com> writes:

Add GC-free closures to D. Less GC reliance means less memory 
fragmentation, enabling lower-level uses of D to use closures.

This has precedent in C blocks and in C++'s lambdas.

James Lu <jamtlu gmail.com> writes:

On Thursday, 5 September 2019 at 14:46:08 UTC, James Lu wrote:
 Add GC-free closures to D. Less GC reliance means less memory 
 fragmentation, enabling lower-level uses of D to use closures.

 This has precedent in C blocks and in C++'s lambdas.

The first question should be, does the current closure semantics 
support GC-free deallocation?

Kagamin <spam here.lot> writes:

On Thursday, 5 September 2019 at 14:50:31 UTC, James Lu wrote:
 The first question should be, does the current closure 
 semantics support GC-free deallocation?

AFAIK, closure is allocated with _d_allocatememory hook. If you 
override it, you can use your preferred allocator there.

a11e99z <black80 bk.ru> writes:

On Thursday, 5 September 2019 at 14:46:08 UTC, James Lu wrote:
 Add GC-free closures to D. Less GC reliance means less memory 
 fragmentation, enabling lower-level uses of D to use closures.

 This has precedent in C blocks and in C++'s lambdas.

1)
 import std;

 auto mul(R)( R r, int n) /* nogc*/ {
     // simple GCed version
     return r.map!( e => e*n);
 
     // more complicated but noGC version
     //return zip( r, n.repeat).map!( z => z[0]*z[1]);
 }
 
 void main() {
     iota( 0, 10).mul( 5).writeln;
 }

2) lambda can capture something that stored in GC 
memory(array,AA,class,new struct,..)
   so for right working (GC:mark/scan) lambda also should be 
allocated in GC memory.
   (opposite: RCed-lambda, emplace, GC.addRange/remove)

a11e99z <black80 bk.ru> writes:

On Thursday, 5 September 2019 at 15:17:04 UTC, a11e99z wrote:
 On Thursday, 5 September 2019 at 14:46:08 UTC, James Lu wrote:
 Add GC-free closures to D. Less GC reliance means less memory 
 fragmentation, enabling lower-level uses of D to use closures.

     // more complicated but noGC version
     //return zip( r, n.repeat).map!( z => z[0]*z[1]);


more complicated visually and thoughtful but machine code 
probably simpler and faster