As in Lean3, the following example is a valid definition
```
def head : {α : Type} → List α → Option α
| _, a::as => some a
| _, _ => none
```
|
||
|---|---|---|
| .. | ||
| bench | ||
| compiler | ||
| elabissues | ||
| ir | ||
| lean | ||
| playground | ||
| plugin | ||
| .gitignore | ||
| common.sh | ||
As in Lean3, the following example is a valid definition
```
def head : {α : Type} → List α → Option α
| _, a::as => some a
| _, _ => none
```
|
||
|---|---|---|
| .. | ||
| bench | ||
| compiler | ||
| elabissues | ||
| ir | ||
| lean | ||
| playground | ||
| plugin | ||
| .gitignore | ||
| common.sh | ||