@@ -224,4 +224,4 @@ Found type of undefined ++ [] (test.hs:2:30-38): [Bool]
...
@@ -224,4 +224,4 @@ Found type of undefined ++ [] (test.hs:2:30-38): [Bool]
```
```
The same effect of holes can then be achieved by using ` {_ undefined _} `.
The same effect of holes can then be achieved by using ` {_ undefined _} `. To return to the conciseness of holes, `__` could be syntactic sugar for `{_ undefined _`}. (Note that defining `__ = {_ undefined _`} in Haskell would not do this. The type would be `forall a. a`.)