7fb35ecf84
This involved, in part, changing the ast::def type so that a def_fn has a "purity" field. This lets the typechecker determine whether functions defined in other crates are pure. It also required updating some error messages in tests. As a test for cross-crate constrained functions, I added a safe_slice function to std::str (slice(), with one of the asserts replaced with a function precondition) and some test cases (various versions of fn-constraint.rs) that call it. Also, I changed "fn" to "pred" for some of the boolean functions in std::uint.
This is a compiler and suite of associated libraries and documentation for the Rust programming language. See LICENSE.txt for terms of copyright and redistribution. See http://github.com/graydon/rust for current development page.