rust-deep-bind

rust-deep-bind helps you bind a value to any function you call, without explicitly passing it through an argument.

You might use this to hold on to configuration, a request or operation ID, or anything for which you would like to use a singleton, but are concerned about all problems that come about with global state.

Example:

```rust contextual!{ MyCounter(MY_COUNTER): u32 = 0 }

println!("{}", MyCounter::clone()); /// 0 MyCounter::replace_within(1, || { println!("{}", MyCounter::clone()); /// 1 }); println!("{}", MyCounter::clone()); /// 0 ```