Re: Small technicality on dynarray

[<HBB...@t-...>]

Daniel J Sebald wrote:

> If I do
> 
>   init_dynarray(foo_array, sizeof(foo), 0, 200);

Then you're already misusing the dynarray module.  It's designed to be 
called like this:

	init_dynarray(&foo_array, sizeof(foo), 200, 200);

Note the '&'.

> That is, it seems it isn't possible to initialize
> the dynarray to size zero.  

There's no point in doing that, so why would you want to?  A dynarray of 
size zero is about as useful as a pointer to nothing.

> It'd nice if one could. It's not of great importance, but for such a
> fundamental utility "consistency" (lack of term) would be nice.

Consistency with what?

> "world.dem", line 13: nextfrom_dynarray: dynarray wasn't initialized!
[...]
> Maybe it should be
> 
> if (size <= 0) graph_error("foo"); this->v = ...

And how would that be any better than the above?  It's just a different 
error message, but no change of actual behaviour.

> It will save a test every time nextfrom_dynarray() is called (which
> is fairly considerable).  Plus, let's say init_dynarray *wasn't*
> called.  

Then size is zero --- that's why the test is done the way it is.

The control struct is supposed to be static, after all, so it's always 
initialized to zero.

 > gp_alloc uses "malloc" which isn't guaranteed to be zero
> (probably system dependent).  

What would that have to do with anything?