jaredpar/VsVim — pull request #1444 by Kazark (2014-09-17 15:49:57+00:00)
Title: Allow many types of expressions on RHS of :let

Support statements such as `:let x=1+2`, 'let x=@a`, `let x=&tabstop`,
etc, by making the right-hand-side of `:let` look for expressions
instead of just literals.

This rounds out what I did with `:echo`.