Merge pull request #2749 from ntoxeg/fix/python-queuevalue

Fix QueueValue in Python API

opencog/cython/opencog/link_value.pyx

@@ -28,12 +28,6 @@ cdef class LinkValue(Value):
         cdef cValuePtr value
         while it != cpp_vector.const_end():
             value = deref(it)
-            if is_a(deref(value).get_type(), types.Value):
-                list.append(create_python_value_from_c_value(value))
-            else:
-                # TODO: Support Atoms as members of LinkValue requires inheriting
-                # Atom from Value and constructor to create Atom from cHandle.
-                raise TypeError('Only Values are supported '
-                                'as members of LinkValue')
+            list.append(create_python_value_from_c_value(value))
             inc(it)
         return list

opencog/cython/opencog/nameserver.pyx

@@ -77,15 +77,23 @@ cdef create_python_value_from_c_value(const cValuePtr& value):
     thismodule = sys.modules[__name__]
     clazz = getattr(thismodule, type_name, None)
     if clazz is not None:
-        return clazz(ptr_holder = ptr_holder)
+        return clazz(ptr_holder=ptr_holder)
 
     # For handling the children types of TruthValue.
     if is_a(value_type, types.TruthValue):
-        return TruthValue(ptr_holder = ptr_holder)
+        return TruthValue(ptr_holder=ptr_holder)
+
+    # For handling the children types of LinkValue.
+    if is_a(value_type, types.LinkValue):
+        return LinkValue(ptr_holder=ptr_holder)
 
     # For handling the children types of Atom.
     if is_a(value_type, types.Atom):
-        return Atom(ptr_holder = ptr_holder)
+        return Atom(ptr_holder=ptr_holder)
+
+    # For handling the children types of Value.
+    if is_a(value_type, types.Value):
+        return Value(ptr_holder=ptr_holder)
 
     raise TypeError("Python API for " + type_name + " is not implemented yet")
 

opencog/cython/opencog/utilities.pxd

@@ -24,4 +24,4 @@ cdef extern from "opencog/cython/executioncontext/Context.h" namespace "opencog"
 # but is installed to "opencog/persist/file/". Cython wants the
 # source location, not the install location.
 cdef extern from "opencog/persist/sexpr/fast_load.h" namespace "opencog":
-    void load_file(const string path, cAtomSpace & atomspace);
+    void c_load_file "opencog::load_file" (const string path, cAtomSpace & atomspace);

opencog/cython/opencog/utilities.pyx

@@ -1,12 +1,12 @@
 from cython.operator cimport dereference as deref
 from libcpp.string cimport string
-from opencog.atomspace cimport AtomSpace, Atom, TruthValue
+from opencog.atomspace cimport AtomSpace, Atom, TruthValue, Value
 from opencog.atomspace cimport cValuePtr, create_python_value_from_c_value
 from opencog.atomspace cimport AtomSpace_factory
 
 from contextlib import contextmanager
 from opencog.atomspace import create_child_atomspace
-from opencog.utilities cimport load_file as c_load_file
+from opencog.utilities cimport c_load_file
 import warnings