Safe Haskell | None |
---|---|
Language | Haskell2010 |
Documentation
Which branch to choose in generic tree representation: left,
straight or right. S
is used when there is one constructor with
one field (something newtype-like).
The reason why we need S
can be explained by this example:
data A = A1 B | A2 Integer
data B = B Bool
Now we may search for A1 constructor or B constructor. Without S
in
both cases path will be the same ([L]).