Re: Small technicality on dynarray

[Daniel J S. <dan...@ie...>]

Hans-Bernhard Bröker wrote:
> 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 '&'.

Naturally.  I was typing away and not paying attention.  The compiler weeds out such typos.

> 
>> 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?

Because in the patch I'm doing I'm placing a dynarray in the plot struct but it may not necessarily be used if no data is read from a file, but instead the plot type is FUNC.

>  A dynarray of 
> size zero is about as useful as a pointer to nothing.

Why assign memory if it isn't going to be used?  I could use a pointer to a dynarray in the plot struct, and then gp_malloc memory for the dynarray only if it is needed.  But that gets to be programming spaghetti.

If one could init the size to zero and on the first "nextfrom_dynarray" the array is extended by this->increment, what's wrong with that?

> 
>> 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?

Again, the issue is that such familiarity with the dynarray code is assumed (e.g., "Why set to zero?  That's silly.") that the test *which is not failsafe as I argued* seems extraneous.

Dan