Fixing C's Biggest Mistake

[H. S. Teoh]

On Thu, Jan 05, 2023 at 10:35:37PM +0000, areYouSureAboutThat via Digitalmars-d wrote:
[...]
> to be honest, I've never needed a static array in D.

:-D  I haven't really used static arrays very much myself, but
occasionally they're useful.  E.g. in one project where I use a lot of
4-element int arrays, using static arrays for them reduces a lot of GC
pressure, and also gives me nice by-value semantics (useful in certain
contexts).


[...]
> in the meantime.. this is hardly .. hard:
> 
> auto myStaticArray = [0, 1].staticArray;
> 
> int[2] myStaticArray = [0, 1].staticArray;
> 
> people can still count.. can't they?

It's not so much about counting, it's about maintainability / mutability
of the code.  For example, if you had a long static array like this:

	int[100] x = [ 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41,
		43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101,
		103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157,
		163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223,
		227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277,
		281, 283, 293, 307, 311, 313, 317, 331, 337, 347, 349,
		353, 359, 367, 373, 379, 383, 389, 397, 401, 409, 419,
		421, 431, 433, 439, 443, 449, 457, 461, 463, 467, 479,
		487, 491, 499, 503, 509, 521, 523, 541 ];

if one day you decide that some elements have to be added/removed from
this array (based on some arbitrary criteria), then you have to recount
and update the length, which, for a long array, isn't a trivial effort.
It's also not very DRY; the compiler can already figure this out for
you, so why make the programmer repeat the same work?

Note that static arrays isn't just arrays of numbers, it could
potentially be an array of some aggregate type with complex initializers
that makes it annoying to have to recount every time you update it.


T

-- 
Жил-был король когда-то, при нём блоха жила.