command eb for example-based grammar conversion; see 'help eb' and the example in examples/animals/QuestionsI.gfe

1 files changed, 59 insertions, 0 deletions

diff --git a/src/compiler/GF/Compile/ExampleBased.hs b/src/compiler/GF/Compile/ExampleBased.hs
new file mode 100644
index 000000000..10d7cdc88
--- /dev/null
+++ b/src/compiler/GF/Compile/ExampleBased.hs
@@ -0,0 +1,59 @@
+module GF.Compile.ExampleBased (parseExamplesInGrammar,configureExBased) where
+
+import PGF
+import PGF.Probabilistic
+
+parseExamplesInGrammar :: ExConfiguration -> FilePath -> IO FilePath
+parseExamplesInGrammar conf file = do
+  src <- readFile file                             -- .gfe
+  let file' = take (length file - 3) file ++ "gf"  -- .gf
+  convertFile conf src file'
+  return file'
+
+convertFile :: ExConfiguration -> String -> FilePath -> IO ()
+convertFile conf src file = do
+  writeFile file "" -- "-- created by example-based grammar writing in GF\n"
+  conv src
+ where
+  conv s = do
+    (cex,end) <- findExample s
+    if null end then return () else do
+      convEx cex
+      conv end
+  findExample s = case s of
+    '%':'e':'x':cs -> return $ getExample cs
+    c:cs -> appf [c] >> findExample cs
+    _ -> return (undefined,s)
+  getExample s = 
+    let 
+      (cat,exend) = break (=='"') s
+      (ex,   end) = break (=='"') (tail exend)
+    in ((unwords (words cat),ex), tail end)  -- quotes ignored
+  pgf = resource_pgf conf
+  lang = language conf 
+  convEx (cat,ex) = do
+    appn "("
+    let typ = maybe (error "no valid cat") id $ readType cat
+    let ts = rank $ parse pgf lang typ ex
+    case ts of
+      []   -> appv ("WARNING: cannot parse example " ++ ex)
+      t:tt -> appn t >> mapM_ (appn . ("  --- " ++)) tt 
+    appn ")"
+  rank ts = case probs conf of
+    Just probs -> [showExpr [] t ++ "  -- " ++ show p | (t,p) <- rankTreesByProbs probs ts]
+    _ -> map (showExpr []) ts
+  appf = appendFile file
+  appn s = appf s >> appf "\n"
+  appv s = appn s >> putStrLn s
+
+data ExConfiguration = ExConf {
+  resource_file :: FilePath,
+  resource_pgf  :: PGF,
+  probs    :: Maybe Probabilities,
+  verbose  :: Bool,
+  language :: Language
+  }
+
+configureExBased :: PGF -> Maybe Probabilities -> Language -> ExConfiguration
+configureExBased pgf mprobs lang = ExConf [] pgf mprobs False lang
+