[new gem]: std.meta & std.typecons

[wilzbach]

From @wilzbach on June 14, 2016 1:26

With std.meta one can do cool stuff like static foreach:

foreach(Type, AliasSeq!(int, double)
 ...

and well std.typecons is D's library version of tuples.

I am not sure yet whether they can combined into a single gem, but imho they are definitely worth explaining.

Copied from original issue: dlang-tour/core#263