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Sat Feb 11 14:20:06 PST 2012
On Saturday, 11 February 2012 at 19:21:49 UTC, Piotr Szturmaj
> Jonathan M Davis wrote:
>> On Saturday, February 11, 2012 19:00:51 q66 wrote:
>>> What's so difficult on that? Slices do not require the GC, you
>>> allocate once, slice many times, deallocate once.
>> With dynamic arrays, the GC owns the memory, and _all_ dynamic
>> arrays are
>> slices. _None_ of them own their own memory. The GC keeps
>> track of whether you
>> have any slices for a particular memory block and deals with
>> freeing up wth
>> the block if you don't. However, if you allocate a dynamic
>> array without the
>> GC, then all of a sudden, it effectively owns its own memory,
>> so the semantics
>> of dealing with arrays and memories changes drastically. What
>> happens when you
>> slice it? Which one owns the memory? What happens when you try
>> and do stuff
>> like popFront on an array? All of a sudden, you have memory
>> which is no longer
>> referenced. It's been leaked.
>> If you have a very careful scheme for handling memory, you
>> _can_ slice arrays
>> without a GC, but you have to worry about all the bookkeeping
>> of keeping track
>> of the originally allocated memory and how many slices
>> reference it so that
>> you can free it when appropriate.
>> Also, you can't concatenate to arrays at all, because that
>> requires the GC.
>> So, you're dealing with a mine field if you try and use D's
>> array capabilities
>> without a GC. Yes, you _can_ use some of them if you're _very_
>> careful, but
>> I'd seriously advise just sticking to using arrays like you
>> would in C except
>> for the fact that arrays know their length.
> Delphi has dynamic arrays and appendable strings without a GC.
> In Delphi pointers and objects are managed manually, but arrays
> and strings are managed automatically (ref counted with
> Copy-On-Write). Take a look at
> http://www.codexterity.com/delphistrings.htm. Maybe some Delphi
> solutions may be used in NoGcD?
It's possible that we just create our own dynamic array similar
to that of std::vector from C++ except using cleaner syntax
available in D. I'd really rather not do that though since it
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