于 11-8-31 下午10:01, Ivan Lazar Miljenovic 写道:

...

Hi, all

parseExp "(,) 3 4 " =>

Right (AppE (AppE (ConE GHC.Unit.(,)) (LitE (IntegerL 3))) (LitE (IntegerL 4)))

where's GHC.Unit.(,) ? GHC.Unit (like all GHC.* modules) is an internal module used by GHC to implement base, containers, etc. The actual definitions of tuples in

On 1 September 2011 11:19, bob zhang wrote: the Prelude "come" from Data.Unit, which for GHC are just re-exported from GHC.Unit: http://haskell.org/ghc/docs/latest/html/libraries/base/src/Data-Tuple.html

Thanks for your quick-reply. I tried this does not work.(simplified) in quasiquoter. import Control.Arrow import Control.Applicative import Prelude hiding ((.), id) import Control.Monad import Control.Category import Data.Derive.All import Data.DeriveTH import Test.QuickCheck import Language.Haskell.TH.Quote import Language.Haskell.TH.Syntax import Language.Haskell.TH.Lib import Language.Haskell.Meta hs = QuasiQuoter { quoteExp = either fail return . parseExp } ---- top-level------- [hs| (,) 3 4 |] will not compile do you know how to fix it ? Thank you ! Best, bob

On 1 September 2011 12:29, bob zhang wrote:

于 11-8-31 下午10:01, Ivan Lazar Miljenovic 写道:

...

On 1 September 2011 11:19, bob zhang  wrote:

...

Hi, all

parseExp "(,) 3 4 " =>

Right (AppE (AppE (ConE GHC.Unit.(,)) (LitE (IntegerL 3))) (LitE (IntegerL 4)))

where's GHC.Unit.(,) ?

GHC.Unit (like all GHC.* modules) is an internal module used by GHC to implement base, containers, etc.  The actual definitions of tuples in the Prelude "come" from Data.Unit, which for GHC are just re-exported from GHC.Unit: http://haskell.org/ghc/docs/latest/html/libraries/base/src/Data-Tuple.html

Hi, I tried   ghc-pkg find-module GHC.Unit --> ghc-prim-0.2.0 :browse GHC.Unit data () = ()

could not find the function (,) exposed,  thanks

Reading the source of Data.Tuple more, it seems that I misunderstood what was going on. GHC.Tuple [1] defines the tuples; GHC.Unit [2] just defines () [1]: http://haskell.org/ghc/docs/latest/html/libraries/ghc-prim-0.2.0.0/GHC-Tuple... [2]: http://haskell.org/ghc/docs/latest/html/libraries/ghc-prim-0.2.0.0/GHC-Unit.... As such, this may very well be a bug somewhere, either haskell-src-meta, template-haskell, or elsewhere. May I ask though why you're trying to use (,) as an explicit constructor in a quasi-quotation? -- Ivan Lazar Miljenovic Ivan.Miljenovic@gmail.com IvanMiljenovic.wordpress.com