• =?UTF-8?B?Tm9yZGzDtnc=?= (15/15) May 18 2016 What's the preferred way in D to implement single-allocation
• Alex Parrill (10/26) May 18 2016 In C it's called a variable-length struct or object. I don't
• =?UTF-8?B?Tm9yZGzDtnc=?= (2/4) May 21 2016 Thanks!

=?UTF-8?B?Tm9yZGzDtnc=?= <per.nordlow gmail.com> writes:

What's the preferred way in D to implement single-allocation 
variable-sized arrays such as

/** Single-Allocation Array. */
struct ArrayN
{
     ubyte length;  // <= maxLength
     size room;     // allocated length
     ubyte[0] data; // `room` number of bytes follows
}

where insertion/deletion typically is done via

     ArrayN* pushBack(ArrayN*, ubyte element);
     ArrayN* popBack(ArrayN*);

which, when needed, will reallocate a new larger/smaller `ArrayN`

?

Further, what's the official name for this structure?

Alex Parrill <initrd.gz gmail.com> writes:

On Wednesday, 18 May 2016 at 21:28:56 UTC, Nordlöw wrote:
 What's the preferred way in D to implement single-allocation 
 variable-sized arrays such as

 /** Single-Allocation Array. */
 struct ArrayN
 {
     ubyte length;  // <= maxLength
     size room;     // allocated length
     ubyte[0] data; // `room` number of bytes follows
 }

 where insertion/deletion typically is done via

     ArrayN* pushBack(ArrayN*, ubyte element);
     ArrayN* popBack(ArrayN*);

 which, when needed, will reallocate a new larger/smaller 
 `ArrayN`

 ?

 Further, what's the official name for this structure?

In C it's called a variable-length struct or object. I don't 
think D implements them, but this could probably work:

struct Foo {
     size_t len;

     ubyte[] data()  property {
         auto thisptr = cast(ubyte*)(&this);
         return thisptr[Foo.sizeof..(Foo.sizeof+len)];
     }
}

=?UTF-8?B?Tm9yZGzDtnc=?= <per.nordlow gmail.com> writes:

On Wednesday, 18 May 2016 at 23:45:07 UTC, Alex Parrill wrote:
 In C it's called a variable-length struct or object. I don't 
 think D implements them, but this could probably work:

Thanks!