RE: infelicity in module imports
| I have often tried, but never succeeded, to understand what | the report says and at the same time unify it with what the | particular compiler I was using actually implemented. Could I ask you to try one more time, with the current draft report? available at http://research.microsoft.com/~simonpj/haskell98-revised I have tried hard to make it easy to understand. I am sure the result is not perfect. If it is not fairly easy to answer your questions below by reading the text, then I would like to improve the text. Can you suggest ways in which it could be made clearer? I've filled in the answers to each of your examples. Simon | Namely what happens in each of the following cases: | Where A is a module exporting the names x, y, p, q, v, w. | import A x, y, p, q, v, w A.x, A.y, A.p, A.q, A.v, A.w | import A() nothing is imported, except instance declarations | import A(x,y) x, y, A.x, A.y | import qualified A A.x, A.y, A.p, A.q, A.v, A.w | import qualified A() nothing is imported, except instance declarations | import qualified A(x,y) A.x A,y | import A hiding () same as import A | import A() hiding () syntactically illegal | import A(x,y) hiding () syntactically illegal | import A hiding (p,q) x, y, v, w A.x, A.y, A.v, A.w | import A() hiding (p,q) syntactically illegal | import A(x,y) hiding (p,q) syntactically illegal | import qualified A hiding () same as import qualified A | import qualified A() hiding () syntactically illegal | import qualified A(x,y) hiding () syntactically illegal | import qualified A hiding (p,q) A.x, A.y, A.v, A.w | import qualified A() hiding (p,q) syntactically illegal | import qualified A(x,y) hiding (p,q) syntactically illegal | | Honestly, in some of these case I do not understand if 1) it | is legal syntax, and if so, 2) what happens, and, if not so, | 3) why not.
Simon Peyton-Jones wrote: | Could I ask you to try one more time, with the current | draft report? available at | http://research.microsoft.com/~simonpj/haskell98-revised I did that before I wrote my e-mail. | Can you suggest ways in which it could be made | clearer? I've filled in the answers to each of your | examples. [...] I think including the full list would take away lots of confusion. But if that is too much, how about including all examples that are legal syntax from below? There were only 10. /Koen.
participants (2)
-
Koen Claessen -
Simon Peyton-Jones