From e02884a94f37871fd2d44cfedd3e9ef9f28f0464 Mon Sep 17 00:00:00 2001
From: Vitor Santos Costa <vsc@dcc.fc.up.pt>
Date: Sat, 24 Mar 2018 22:56:52 +0000
Subject: [PATCH] error handling

---
 CXX/yapi.cpp                        | 15 +++----
 packages/python/swig/yap4py/yapi.py | 65 +++++++++++++++--------------
 2 files changed, 40 insertions(+), 40 deletions(-)

diff --git a/CXX/yapi.cpp b/CXX/yapi.cpp
index 85b6e6fb3..0802b719d 100644
--- a/CXX/yapi.cpp
+++ b/CXX/yapi.cpp
@@ -437,6 +437,7 @@ bool YAPEngine::call(YAPPredicate ap, YAPTerm ts[]) {
     LOCAL_RestartEnv = &buf;
     if (sigsetjmp(*LOCAL_RestartEnv, false)) {
         std::cerr << "Restart\n";
+        throw *new YAPError();
       //q.e = new YAPError();
     }
     // don't forget, on success these bindings will still be there);
@@ -490,7 +491,7 @@ bool YAPEngine::mgoal(Term t, Term tmod) {
     if (sigsetjmp(*LOCAL_RestartEnv, false)) {
       //      PyEval_RestoreThread(_save);
   std::cerr << "Restart\n";
-        //throw new YAPError();
+      throw *new YAPError();
     }
     // don't forget, on success these guys may create slots
     __android_log_print(ANDROID_LOG_INFO, "YAPDroid", "exec  ");
@@ -567,10 +568,7 @@ Term YAPEngine::fun(Term t) {
     sigjmp_buf buf, *oldp = LOCAL_RestartEnv;
     LOCAL_RestartEnv = &buf;
     if (sigsetjmp(*LOCAL_RestartEnv, false)) {
-      //  throw new YAPError();
-      LOCAL_RestartEnv = oldp;
-      RECOVER_MACHINE_REGS();
-      return 0;
+      throw *new YAPError();
     }
     // don't forget, on success these guys may create slots
     __android_log_print(ANDROID_LOG_INFO, "YAPDroid", "exec  ");
@@ -693,7 +691,7 @@ bool YAPQuery::next() {
       return false;
     LOCAL_RestartEnv = &buf;
     if (sigsetjmp(*LOCAL_RestartEnv, false)) {
-      //e = new YAPError();
+      throw *new YAPError();
     }
     // don't forget, on success these guys may create slots
     __android_log_print(ANDROID_LOG_INFO, "YAPDroid", "exec  ");
@@ -712,10 +710,9 @@ bool YAPQuery::next() {
     }
     q_state = 1;
     if ((terr = Yap_PeekException())) {
-        LOCAL_RestartEnv = &buf;
+      throw * new YAPError();
 
-        result = false;
-    }
+      }
     __android_log_print(ANDROID_LOG_INFO, "YAPDroid", "out  %d", result);
 
     if (!result) {
diff --git a/packages/python/swig/yap4py/yapi.py b/packages/python/swig/yap4py/yapi.py
index a26d3b007..56ba37a59 100644
--- a/packages/python/swig/yap4py/yapi.py
+++ b/packages/python/swig/yap4py/yapi.py
@@ -144,38 +144,41 @@ class YAPShell:
         #    if not isinstance(eq[0],str):
         #        print( "Error: Variable Name matches a Python Symbol")
         #        return
-        self.do_ask = True
-        engine = self.engine
-        bindings = []
-        g = python_query(self, query)
-        if not self.q:
-            self.q = Query( engine, g )
-        for bind in self.q:
-            bindings += [bind]
-            if self.do_ask:
-                print(bindings)
-                bindings = []
+        try:
+            engine = self.engine
+            bindings = []
+            loop = False
+            g = python_query(self, query)
+            if not self.q:
+                self.q = Query( engine, g )
+            for bind in self.q:
+                bindings += [bind]
+                if loop:
+                    continue
+                if not self.q:
+                    break
                 s = input("more(;),  all(*), no(\\n), python(#) ?").lstrip()
-            else:
-                s = ";"
-            if s.startswith(';') or s.startswith('y'):
-                continue
-            elif s.startswith('#'):
-                try:
-                    exec(s.lstrip('#'))
-                except:
-                    raise
-            elif s.startswith('*') or s.startswith('a'):
-                self.do_ask = False
-                continue
-            else:
-                break
-        if self.q:
-            self.os = query
-        if bindings:
-            return True,bindings
-        print("No (more) answers")
-        return False, None
+                if s.startswith(';') or s.startswith('y'):
+                    continue
+                elif s.startswith('#'):
+                    try:
+                        exec(s.lstrip('#'))
+                    except:
+                        raise
+                elif s.startswith('*') or s.startswith('a'):
+                    loop = True
+                    continue
+                else:
+                    break
+            if self.q:
+                self.os = query
+            if bindings:
+                return True,bindings
+            print("No (more) answers")
+            return False, None
+        except e:
+            print("Exception")
+            print(e)
 
 
     def live(self, engine, **kwargs):