Without this fix, the parser wrongly turns the following:
```
{
let a = Void
a
}
let _ = True
True
```
into the following:
```
let a = Void
a
let _ = True
True
```
Which in this particular example looks benign. But now takes something
more _real-world_:
```
{
let scope, output <- for_each_2(scopes, other_outputs)
Void
}
let _ = True
True
```
This would lead to the the entire sequence that follows the
backpassed continuation to be added to the continuation; here
ultimately causing a type unification error (since for_each_2 is
expected to yield Void, not Bool).
This is utterly confusing.. and dangerous.
Signed-off-by: KtorZ <matthias.benkort@gmail.com>
KtorZ