Christian, I incorporated your approach of defining the ADT, and Michael's
suggestions into
*tada*
http-types 0.2.0 - http://hackage.haskell.org/package/http-types-0.2.0
Features:
* StdMethod is an enumeration without OtherMethod constructor, containing
only RFC 2616 standard HTTP methods.
* parseMethod :: ByteString -> Either ByteString StdMethod (I think the type
says all).
* There are a few pre-defined Headers (headerAccept...)
* urlEncode / urlDecode
* Parsing and rendering of query strings (Query / SimpleQuery).
I hope this is closer to what most people would consider a nice version.
Aristid
2011/2/4 Christian Maeder
Am 04.02.2011 11:49, schrieb Christian Maeder:
The disadvantage for just strings are possible spelling errors. With constants or constructors spelling errors are detected by the compiler (but you still can confuse constants having the same type).
Therefore just having
type Method = ByteString
is also less safe, because constants for methods and i.e. header names (if they are also just byte strings) can be mixed up without type errors.
Better would be a newtype wrapper around byte strings (or just strings):
newtype Method = M ByteString
But I do not want to interfere with Michael Snoymann's compatibility issues for wai.
Cheers Christian