Hi.
I believe I'm using parsec 3.0.1, although I already fixed the imports (even
thou they were working).
Thanks for the references, specially the parsec User Guide - it saved my
life, in 30 minutes I actually *understood* my mistake and fixed it. Now my
code and it compiles and makes sense, even though it's a bit useless, since
it has no return values [yet].
I'll take a look at UUAG and Tiger. However, since this is a simple college
assignment, I want my compiler to be as simple as possible but in a way I
understand what I'm doing, so I'll probably be doing it by hand.
Fernando Henrique Sanches
On Mon, Nov 30, 2009 at 2:58 PM, Stephen Tetley
Hi Fernando
Which version of Parsec are you using, the one that ships with GHC or Parsec 3?
I would imagine whichever you one you are using you have the imports wrong for these modules:
import Text.Parsec.Pos import Text.Parsec.Prim
should be ...
import Text.ParserCombinators.Parsec.Pos import Text.ParserCombinators.Parsec.Prim
Also it seems like an applicative instance for Parsec's GenParser monad is missing. This isn't defined for parsec-2.1.0.1, people seem to define it themselves:
-- The Applicative instance for every Monad looks like this. instance Applicative (GenParser s a) where pure = return (<*>) = ap
... you will need `ap` from Control.Monad in scope.
Also there is a pdf document for Parsec (should be available from Daan Leijen's home page) that covers separate scanners, it has quite a lot more documentation than Parsec's Haddock docs.
For semantic analysis I'd highly recommend UUAG, it is well documented and used for a large compiler (EHC). There is also a version of Andrew Appel's Tiger language written with it that is much smaller and more comprehensible, the version on Hackage doesn't seem to contain the attribute grammar source but it is available here:
http://www.cs.uu.nl/wiki/bin/view/HUT/TigerCompiler
http://www.cs.uu.nl/wiki/bin/view/HUT/AttributeGrammarSystem
Best wishes
Stephen