### Rust Version

* Use the output of `rustc -V`

### Affected Version of clap

* Can be found in Cargo.lock of your project (i.e. `grep clap Cargo.lock`)

### Bug or Feature Request Summary


### Expected Behavior Summary


### Actual Behavior Summary


### Steps to Reproduce the issue


### Sample Code or Link to Sample Code


### Debug output

Compile clap with cargo features `"debug"` such as:

```toml
[dependencies]
clap = { version = "2", features = ["debug"] }
```


 Debug Output 

Paste Debug Output Here

