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# `abort` and `unwind`
The previous section illustrates the error handling mechanism `panic`. Different code paths can be conditionally compiled based on the panic setting. The current values available are `unwind` and `abort`.
Building on the prior lemonade example, we explicitly use the panic strategy to exercise different lines of code.
```rust,editable,mdbook-runnable
fn drink(beverage: &str) {
// You shouldn't drink too much sugary beverages.
if beverage == "lemonade" {
if cfg!(panic="abort"){ println!("This is not your party. Run!!!!");}
else{ println!("Spit it out!!!!");}
}
else{ println!("Some refreshing {} is all I need.", beverage); }
}
fn main() {
drink("water");
drink("lemonade");
}
```
Here is another example focusing on rewriting `drink()` and explicitly use the `unwind` keyword.
```rust,editable
#[cfg(panic = "unwind")]
fn ah(){ println!("Spit it out!!!!");}
#[cfg(not(panic="unwind"))]
fn ah(){ println!("This is not your party. Run!!!!");}
fn drink(beverage: &str){
if beverage == "lemonade"{ ah();}
else{println!("Some refreshing {} is all I need.", beverage);}
}
fn main() {
drink("water");
drink("lemonade");
}
```
The panic strategy can be set from the command line by using `abort` or `unwind`.
```console
rustc lemonade.rs -C panic=abort
```
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