On Fri, May 25, 2012 at 2:51 PM, Sam Lindley <sam.lind...@ed.ac.uk> wrote: > Template Haskell supports antiquotation for built-in quasiquotes, e.g.: > > [| \x -> x + $([|3 * 4|]) |] > > However, as far as I can tell, there is no way of supporting antiquotation > in user-defined quasiquoters, because the only way to specify a new > quasiquoter is through a quoteExp function of type String -> Q Exp. Of > course, it is perfectly possible to write a parser for some fragment of > Haskell inside your quoteExp function, but that seems crazy given that > Template Haskell or rather GHC already implements a parser for the whole > language. > > I know about Language.Haskell.Exts.Parser in haskell-src-exts, which > provides parseExp :: String -> ParseResult Exp, but that Exp is a different > type to the one provided by Template > Haskell.<http://hackage.haskell.org/packages/archive/haskell-src-exts/1.9.0/doc/html/Language-Haskell-Exts-Syntax.html#t:Exp> > I'm also aware of Dominic Orchard's syntax-trees package, which supports > converting between the two representations using a cunning hack that > pretty-prints the haskell-src-exts representation to a string and uses > Template Haskell to parse it back. > > Is there a saner way of simulating antiquotation in user-defined > quasiquoters? >
Have you looked at: http://hackage.haskell.org/package/haskell-src-exts-qq http://hackage.haskell.org/package/haskell-src-meta The might help you pull something together. Antoine > Sam > > > -- > The University of Edinburgh is a charitable body, registered in > Scotland, with registration number SC005336. > > > _______________________________________________ > Haskell-Cafe mailing list > Haskell-Cafe@haskell.org > http://www.haskell.org/mailman/listinfo/haskell-cafe _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
