The tutorial's section on pattern matching (http://static.rust-lang.org/doc/master/tutorial.html#pattern-matching) shows some patterns without any variable-bindings in them, and then mentions "so long as every pattern binds the same set of variables". This caused my partner, with whom I am currently working through the tutorial, to stop because she thought she must have missed something. a few sentences later in the tutorial variable bindings are introduced by example, and explained.