dtemplate Tuple, add a ctor taking num elements

[ghost]

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[JinShil]

We're trying to incrementally improve the dmd code base. One of the things we prefer is that any new public symbols have full DDoc headers with a description, params, and returns. I admit it's selectively enforced, and I don't think it should prevent a PR from being merged, but we would like contributors to put forth the effort. 😉

EDIT: Also please see https://dlang.org/dstyle.html#phobos_documentation. It's different from the rest of DMD but it's the style we want to incrementally migrate to (at least some of us).

[ghost]

Yes of course. This is just a bit strange to start doing it when the practice is not generalized.
I had to amend anyway since the default ctor can be avoided using a default numObjects.

[JinShil]

See item 12 here: https://forum.dlang.org/post/p6oibo$1lmi$1@digitalmars.com

I don't really like it, but you can avoid the default parameter by forwarding to a parameter-less constructor in the body of this constructor.

Edit: Of course, he also says "Minimize use of overloading." and "treating the above as sacred writ is a huge mistake.", so maybe we should keep it a default parameter.

[ghost]

Yes but it's either that or a useless default ctor since default ctors ares till not auto generated ;)

[JinShil]

I'm guessing the preference would be:

/**
Constructs a new instance.
*/
extern (D) this()
{
    this(0);
}

/**
Constructs a new instance.

Params:
    numObjects = The initial number of objects.
*/
extern (D) this(size_t numObjects)
{
    objects.setDim(numObjects);
}

[ghost]

No, with empty parens this would mean two useless call: other ctor overload and then objects.setDim.

[JinShil]

Please remove the prepended *.

[JinShil]

Newline before params

[jacob-carlborg]

We really should have an updated style guide for all this that is linked from the readme or the contribute documentation.

[WalterBright]

This line is spurious, as that's what a this constructor does. Please delete it.

[ghost]

ok done.

[jacob-carlborg]

I think all documented symbols should have a summary. This allows to automatically generate an index table, i.e. something like the table at the top of [1].

[1] https://dlang.org/phobos/std_array.html