mozilla/rust — pull request #7156 by Dretch (2013-06-15 17:07:27+00:00)
Title: Add IterBytes impls for float/f32/f64. This allows creating HashMaps with floats as keys.

It can sometimes be useful to have maps/sets of floating point values.

Doing arithmetic with floats and then using them as keys is, of course, not a good idea.