proposal #3335: make some Applicative functions into methods, and split off Data.Functor

Ross Paterson ross at
Wed Aug 19 16:21:25 EDT 2009

On Wed, Aug 19, 2009 at 01:04:13PM -0400, Edward Kmett wrote:
> (*>) and (<*) could be used to apply recognizing parsers for the
> discarded half.  This makes a huge gain for uu-parsinglib.
> uu-parsinglib's P_m monad could be extended just as it has done with
> P_f and P_h to also wrap its existing R monad, which would let it
> apply the parser as a recognizer efficiently.
> And for parsimony it allows me to treat that side of the alternative
> grammar as a right seminearring ignoring the argument, this increases
> sharing opportunities for my grammar fragments, because pure nodes in
> recognizers can be treated as epsilons in the grammar and safely elided.


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