If I have this right, Stream is a monad transformer. Stream s m t means that it parses 's', is stacked with monad 'm' and has a result of type 't' So Identity is a monad, the simplest monad, defined as such: newtype Indentity t = Identity { runIdentity :: t } It's the identity monad, that does nothing special but wrapping its result. 2011/10/8 Captain Freako <capn.freako@gmail.com>
Hi all,
In this definition from the Parsec library:
parse :: (Stream s Identity t) => Parsec s () a -> SourceName -> s -> Either ParseError aparse p = runP p ()
what's the significance of `Identity t'? (`t' isn't used anywhere.)
Thanks, -db
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