Other language features you'd want in D

[Denton Cockburn]

What are some features found in other languages that you believe would be
really good to have in D?

These can be language features or library features.

It shouldn't be any of the general items found in the comparison FAQ (like
Multiple inheritance).  Something that's relatively nice and specific.

e.g.
I miss multiple value returns found in Lisp.  Out parameters are not
nearly as nice.

P.S. Has anyone thought to write a document on some of the struct tricks
that I've been seeing mentioned?  They exploit struct features, but I
think only a select few understand them.