rust-lang/rust — pull request #19587 by huonw (2014-12-06 01:48:51+00:00)
Title: Feature-gate explicit unboxed closure method calls & manual impls,

detect UFCS drop and allow UFCS methods to have explicit type parameters.

Work towards #18875.

Since code could previously call the methods & implement the traits
manually, this is a

[breaking-change]

Closes #19856. Closes #19375.