Dear all, S. Alexander Jacobson wrote:
I don't think I'm the only one confused here. Henrik Nilson in his paper on adding GADTs to Yampa comments that: ... In particular, GADTs are just what is needed to address the problem discussed above since the key idea is to allow constructors that have more specific types than usual, and to take that extra type information into account in individual case branches. GADTs would no doubt also offer an interesting alternative to the methods described by Baars and Swierstra [1] and Hughes [19].
[1] and [19] are papers about Arrows.
I categorically deny being confused! :-) The comment refers to the methods Baars, Swierstra, and Hughes employ to encode type equality in order to be able to perform optimizations along similar lines as outlined in my paper. I was not at all proposing to use GADTs in place of arrows, and I cannot really see how the quote can be read as suggesting that. As Neil has already said: GADTs and arrows are just different kinds of entities. Best, /Henrik -- Henrik Nilsson School of Computer Science and Information Technology The University of Nottingham nhn@cs.nott.ac.uk This message has been checked for viruses but the contents of an attachment may still contain software viruses, which could damage your computer system: you are advised to perform your own checks. Email communications with the University of Nottingham may be monitored as permitted by UK legislation.