blob: 48b09cee23acc6da777fe14e3457d7c3b87f4209 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
|
----------------------------------------------------------------------
-- |
-- Maintainer : PL
-- Stability : (stable)
-- Portability : (portable)
--
-- > CVS $Date: 2005/04/21 16:21:57 $
-- > CVS $Author: bringert $
-- > CVS $Revision: 1.4 $
--
-- Adding coercion functions to a MCFG if necessary.
-----------------------------------------------------------------------------
module GF.Conversion.SimpleToMCFG.Coercions
(addCoercions) where
import GF.System.Tracing
import GF.Infra.Print
import GF.Formalism.Utilities
import GF.Formalism.GCFG
import GF.Formalism.MCFG
import GF.Conversion.Types
import GF.Data.SortedList
import Data.List (groupBy)
----------------------------------------------------------------------
addCoercions :: EGrammar -> EGrammar
addCoercions rules = coercions ++ rules
where (allHeads, allArgs) = unzip [ ((head, lbls), nubsort args) |
Rule (Abs head args _) (Cnc lbls _ _) <- rules ]
allHeadSet = nubsort allHeads
allArgSet = union allArgs <\\> map fst allHeadSet
coercions = tracePrt "SimpleToMCFG.Coercions - nr. MCFG coercions" (prt . length) $
concat $
tracePrt "SimpleToMCFG.Coerciions - nr. MCFG coercions per category"
(prtList . map length) $
combineCoercions
(groupBy sameECatFst allHeadSet)
(groupBy sameECat allArgSet)
sameECatFst a b = sameECat (fst a) (fst b)
combineCoercions [] _ = []
combineCoercions _ [] = []
combineCoercions allHeads'@(heads:allHeads) allArgs'@(args:allArgs)
= case compare (ecat2scat $ fst $ head heads) (ecat2scat $ head args) of
LT -> combineCoercions allHeads allArgs'
GT -> combineCoercions allHeads' allArgs
EQ -> makeCoercion heads args : combineCoercions allHeads allArgs
makeCoercion heads args
= [ Rule (Abs arg [head] coercionName) (Cnc lbls [lbls] lins) |
(head@(ECat _ headCns), lbls) <- heads,
let lins = [ Lin lbl [Cat (head, lbl, 0)] | lbl <- lbls ],
arg@(ECat _ argCns) <- args,
argCns `subset` headCns ]
|
