From ca5b62a4099a7891f23d7d20dec05207b7d4ab06 Mon Sep 17 00:00:00 2001
From: Jed Barber <jjbarber@y7mail.com>
Date: Sun, 7 Dec 2014 19:48:48 +1100
Subject: del instruction added

---
 src/Grasp/Interpreter.hs | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

(limited to 'src/Grasp/Interpreter.hs')

diff --git a/src/Grasp/Interpreter.hs b/src/Grasp/Interpreter.hs
index 0d24ce1..bca167a 100644
--- a/src/Grasp/Interpreter.hs
+++ b/src/Grasp/Interpreter.hs
@@ -112,7 +112,22 @@ newI = do
 
 
 delI :: GraspM ()
-delI = GMonad.updateIP
+delI = do
+    curNode <- GMonad.peekIP >>= return . Maybe.fromJust
+
+    tailNodes <- GMonad.nodesOut (EL.mk "tail") curNode
+    headNodes <- GMonad.nodesOut (EL.mk "head") curNode
+    labelNodes <- GMonad.nodesOut (EL.mk "label") curNode
+
+    Monad.when (length tailNodes /= 0) (do
+        input <- mapM GMonad.edgesOut tailNodes >>= return . concat
+        let labels = map (EL.mk . IN.toString . GN.toInst) labelNodes
+            heads = map GN.toNode headNodes
+            result = filter (\x -> (length headNodes == 0 || GE.toDest x `elem` heads) &&
+                                    (length labelNodes == 0 || GE.toLabel x `elem` labels)) input
+        GMonad.delEdges result )
+
+    GMonad.updateIP
 
 
 
-- 
cgit