Files
gf-core/src-3.0/GF/GFCC/Generate.hs
2008-05-21 13:10:54 +00:00

71 lines
2.2 KiB
Haskell

module GF.GFCC.Generate where
import GF.GFCC.Macros
import GF.GFCC.DataGFCC
import GF.GFCC.CId
import qualified Data.Map as M
import System.Random
-- generate an infinite list of trees exhaustively
generate :: GFCC -> CId -> Maybe Int -> [Exp]
generate gfcc cat dp = concatMap (\i -> gener i cat) depths
where
gener 0 c = [tree (AC f) [] | (f, ([],_)) <- fns c]
gener i c = [
tr |
(f, (cs,_)) <- fns c,
let alts = map (gener (i-1)) cs,
ts <- combinations alts,
let tr = tree (AC f) ts,
depth tr >= i
]
fns c = [(f,catSkeleton ty) | (f,ty) <- functionsToCat gfcc c]
depths = maybe [0 ..] (\d -> [0..d]) dp
-- generate an infinite list of trees randomly
genRandom :: StdGen -> GFCC -> CId -> [Exp]
genRandom gen gfcc cat = genTrees (randomRs (0.0, 1.0 :: Double) gen) cat where
timeout = 47 -- give up
genTrees ds0 cat =
let (ds,ds2) = splitAt (timeout+1) ds0 -- for time out, else ds
(t,k) = genTree ds cat
in (if k>timeout then id else (t:))
(genTrees ds2 cat) -- else (drop k ds)
genTree rs = gett rs where
gett ds cid | cid == mkCId "String" = (tree (AS "foo") [], 1)
gett ds cid | cid == mkCId "Int" = (tree (AI 12345) [], 1)
gett [] _ = (tree (AS "TIMEOUT") [], 1) ----
gett ds cat = case fns cat of
[] -> (tree (AM 0) [],1)
fs -> let
d:ds2 = ds
(f,args) = getf d fs
(ts,k) = getts ds2 args
in (tree (AC f) ts, k+1)
getf d fs = let lg = (length fs) in
fs !! (floor (d * fromIntegral lg))
getts ds cats = case cats of
c:cs -> let
(t, k) = gett ds c
(ts,ks) = getts (drop k ds) cs
in (t:ts, k + ks)
_ -> ([],0)
fns cat = [(f,(fst (catSkeleton ty))) | (f,ty) <- functionsToCat gfcc cat]
{-
-- brute-force parsing method; only returns the first result
-- note: you cannot throw away rules with unknown words from the grammar
-- because it is not known which field in each rule may match the input
searchParse :: Int -> GFCC -> CId -> [String] -> [Exp]
searchParse i gfcc cat ws = [t | t <- gen, s <- lins t, words s == ws] where
gen = take i $ generate gfcc cat
lins t = [linearize gfcc lang t | lang <- cncnames gfcc]
-}