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  1. import std.stdio;
  2. import std.c.stdlib;
  3.  
  4. T o_new(T, U...)(U args) if (is(T == class))
  5. {
  6.     size_t sz  = __traits(classInstanceSize, T);
  7.     void[] mem = calloc(sz, byte.sizeof)[0 .. sz];
  8.  
  9.     if (mem.length < sz) return null;
  10.  
  11.     auto ret = cast(T) mem.ptr;
  12.     (cast(byte[]) mem)[0 .. sz] = typeid(T).init[];
  13.  
  14.     static if (is(typeof(ret.__ctor(args))))
  15.         ret.__ctor(args);
  16.     else
  17.     {
  18.         static assert(
  19.             args.length == 0 && !is(typeof(&T.__ctor)),
  20.             "No ctor with arguments " ~ U.stringof ~
  21.             " present for an object of type " ~ T.stringof
  22.         );
  23.     }
  24.  
  25.     return ret;
  26. }
  27.  
  28. void o_delete(T)(T val) if (is(T == class))
  29. {
  30.     static if (is(typeof(val.__dtor())))
  31.         val.__dtor();
  32.  
  33.     free(cast(void*) val);
  34. }
  35.  
  36. class Foo
  37. {
  38.     void bah() { writeln("foo"); }
  39.  
  40.     ~this()
  41.     {
  42.         writeln("dtor");
  43.     }
  44. }
  45.  
  46. void main()
  47. {
  48.     Foo x = o_new!Foo();
  49.     x.bah();
  50.  
  51.     o_delete(x);
  52. }
  53.  
Success #stdin #stdout 0.01s 2120KB
comments (?)
stdin 
Standard input is empty
stdout 
foo
dtor
https://ideone.com/2qAxy
language:
D (dmd 2.085.0)
created:
14 years ago
visibility:
public

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