linearization by chunks in the GF shell: a new command 'lc' needed because 'l' requires type checking and trees with metavariable function heads don't type check. This will hopefully be a temporary command.

src/compiler/GF/Command/TreeOperations.hs

@@ -1,6 +1,7 @@
 module GF.Command.TreeOperations (
   treeOp,
-  allTreeOps
+  allTreeOps,
+  treeChunks
   ) where
 
 import PGF
@@ -30,6 +31,8 @@ allTreeOps pgf = [
       Left  $ concatMap subtrees)),
    ("funs",("return all fun functions appearing in the tree, with duplications",
       Left  $ concatMap funNodes))
+---   ("chunks",("return all chunks, i.e. maximal subtrees where the top node is not a metavariable",
+---      Left  $ concatMap treeChunks)) --- a tree with ? head does not type check anyway AR 5/11/2013
   ]
 
 largest :: [Expr] -> [Expr]
@@ -42,6 +45,15 @@ smallest = sortBy (\t u -> compare (size t) (size u)) where
     EApp e1 e2 -> size e1 + size e2 + 1
     _ -> 1
 
+treeChunks :: Expr -> [Expr]
+treeChunks = snd . cks where
+  cks t = case unAppForm t of
+    (EFun f, ts) -> case unzip (map cks ts) of 
+       (bs,_) | and bs      -> (True, [t])
+       (_,cts)              -> (False,concat cts)
+    (EMeta _, ts)           -> (False,concatMap (snd . cks) ts)
+    _                       -> (True, [t])
+
 subtrees :: Expr -> [Expr]
 subtrees t = t : case unApp t of
   Just (f,ts) -> concatMap subtrees ts