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| author | aarne <aarne@cs.chalmers.se> | 2008-11-11 09:21:59 +0000 |
|---|---|---|
| committer | aarne <aarne@cs.chalmers.se> | 2008-11-11 09:21:59 +0000 |
| commit | db18350b1e55f7edfca8f02b0b233a6a7dcbb1ec (patch) | |
| tree | 525fd7fc741c53a4021d1edd9538452ee388e4d3 /examples/tutorial/embedded/TransferDef.hs | |
| parent | ca59050abc8efccfb59b93cfbd8da93556605928 (diff) | |
fixed some tutorial grammars and updated embedded section (JavaScript and web TODO)
Diffstat (limited to 'examples/tutorial/embedded/TransferDef.hs')
| -rw-r--r-- | examples/tutorial/embedded/TransferDef.hs | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/examples/tutorial/embedded/TransferDef.hs b/examples/tutorial/embedded/TransferDef.hs new file mode 100644 index 000000000..37d81c6dc --- /dev/null +++ b/examples/tutorial/embedded/TransferDef.hs @@ -0,0 +1,26 @@ +module TransferDef where + +import PGF (Tree) +import Query -- generated from GF + +transfer :: Tree -> Tree +transfer = gf . answer . fg + +answer :: GQuestion -> GAnswer +answer p = case p of + GOdd x -> test odd x + GEven x -> test even x + GPrime x -> test prime x + +value :: GObject -> Int +value e = case e of + GNumber (GInt i) -> fromInteger i + +test :: (Int -> Bool) -> GObject -> GAnswer +test f x = if f (value x) then GYes else GNo + +prime :: Int -> Bool +prime x = elem x primes where + primes = sieve [2 .. x] + sieve (p:xs) = p : sieve [ n | n <- xs, n `mod` p > 0 ] + sieve [] = [] |
