Add TypeInfo functions analogs

[denis-sh]

It is needed for various Phobos functions.

Requires pull #924.

[alexrp]

What functions need these, though?

[denis-sh]

What functions need these, though?

move, destruct, and emplace (when I will finish its incredibly complicated final version).

[denis-sh]

Tweaked setInitialState (primary for CTFE): do not call mem* functions if there is postblit but no destructor. Added comment about it.

[denis-sh]

Rebased and moved to std.conv.

[andralex]

This doesn't say what the function does, only how it can be useful to advanced programmers.

[denis-sh]

Phobos' programmers must be advanced.

[dnadlinger]

I would add that »dealing with tricky xyz« doesn't strike me as particularly descriptive (if you are just reading the docs, what tricky aspects of .init does it avoid)

[denis-sh]

All tricky aspects as TypeInfo has lots of them.

[denis-sh]

Fixed terrible name bug: renamed callCopyConstructors to callPostblits as it calls postblits, not copy constructors (big thanks to David).
Also other changes requested by David.

[andralex]

Since this is non-public, ddoc should not be generated for it.

[denis-sh]

Yes. And where is the problem?

[jmdavis]

Don't use a ddoc comment if it's not supposed to end up in the documentation. Use a regular comment.

[DmitryOlshansky]

So it's been a year. Some stuff changed. Druntime already contains templates no problem.

@andralex
Should it put these primitives into druntime? What are other objections?

As this goes in connection to other @denis-sh pull I'll let him judge on whether or not to pursue this on its own.

[dnadlinger]

tricky? If a user doesn't know why, this comment doesn't help them at all. Oh, it's package anyway, so doc comment quality doesn't matter that much.

[monarchdodra]

Druntime already contains templates no problem.

That's a misguided comment. druntime can have templates, and has some trivial templates. However, It has no access to traits or typetuple, making anything that does any kind of introspection, virtually impossible.

Currently, there is (afaik) nothing in druntime that has a behavior dependent on introspection: This why we have the whole fiasco with "Is array appending safe or nothrow? Who knows!?".

[DmitryOlshansky]

Closing as there is no activity for a whole year.