Deferrer

defer! macro for deferring functions.

Example

```rust use deferrer::*; use std::cell::RefCell;

let mut s = RefCell::new(String::from("Hello")); { defer!( || s.borrowmut().pushstr(" world!") ); asserteq!(*s.borrow(), "Hello"); } asserteq!(*s.borrow(), "Hello world!"); ```