On 2 November 2010 22:40, Michael Litchard
fromAttrib :: (Show str, Eq str, StringLike str) => str -> Tag str -> str
seems to say "fromAttrib takes two parameters (I know it doesn't literally take two), one str (with the constraints in parenthesis to the left) and one str of type Tag, giving back a str. Then I look at the above code sample and can't match the two up.
It's one string-like (String, ByteString, etc.) value `str`, and one *Tag* which contains, in its attributes and text contents, string-like values, also `str`. It extracts this `str` from the `Tag str` (tag of string-like `str`). The reason Tag is parametrized over the String type is so that you can use TagSoup with String (normal case), or ByteString for when you need speed, or Text, or whatever string type you need that implements the StringLike type.