Shopping for template languages

[An Pham]

On Wednesday, 7 August 2024 at 20:26:07 UTC, matheus wrote:
>
> Anyway, I wish there was a C version or a D option for auto 
> free after end of scope for memory manually allocated for 
> example.
>
> Matheus.

No need language feature - here is auto free after scope
compile with -debug option

import core.stdc.stdlib : malloc;
import std.stdio : writeln;

struct Foo
{
     int x;
}

struct Owned(T)
{
     this(void* v) nothrow @nogc
     {
         debug writeln("constructor");
         this.v = cast(T*)v;
     }

     ~this() nothrow @nogc
     {
         debug writeln("destructor");
         import core.stdc.stdlib : free;
         if (v)
         {
             free(v);
             debug writeln("free");
         }
     }

     static typeof(this) malloc() nothrow @nogc // same attribute 
as stdlib.malloc
     {
         return typeof(this)(.malloc(T.sizeof));
     }

     T* v;
     alias this=v;
}

void main()
{
     { // Simulate scope
     auto foo = Owned!Foo(malloc(Foo.sizeof));
     foo.x = 10;
     assert(foo.x == 10);
     writeln(foo.x);
     }

     { // Simulate scope
     auto foo = Owned!Foo.malloc;
     foo.x = 100;
     assert(foo.x == 100);
     writeln(foo.x);
     }
}