steveklabnik/rust_for_rubyists — pull request #100 by cdwort (2014-08-19 22:01:42+00:00)
Title: Pass reference pointer not box pointer

This code sample triggers a compiler error as we are passing a box
when plus_one expects a reference.

Obviously, this is one of many ways to fix this problem. Another would be
to have plus_one accept a Box, but that would require altering
the text accompanying the code and is more than plus_one needs.