Fixed #68: Implement SheerkaQL

Fixed #70: SheerkaFilterManager : Pipe functions
Fixed #71: SheerkaFilterManager : filter_objects
Fixed #75: SheerkaMemory: Enhance memory() to use the filtering capabilities
Fixed #76: SheerkaEvaluateConcept: Concepts that modify the state of the system must not be evaluated during question

src/core/sheerka/Sheerka.py

@@ -109,6 +109,7 @@ class Sheerka(Concept):
         self.enable_commands_backup = True
 
         self.methods_with_context = {"test_using_context"}  # only the names, the method is defined in sheerka_methods
+        self.pipe_functions = set()
         self.sheerka_methods = {
             "test": SheerkaMethod(self.test, False),
             "test_using_context": SheerkaMethod(self.test_using_context, False),
@@ -145,13 +146,22 @@ class Sheerka(Concept):
         if as_name is None:
             as_name = bound_method.__name__
 
+        if as_name.startswith("pipe_"):
+            as_name = as_name[5:]
+            is_pipe_function = True
+        else:
+            is_pipe_function = False
+
         if visible:
             signature = inspect.signature(bound_method)
             if len(signature.parameters) > 0 and list(signature.parameters.keys())[0] == "context":
                 self.methods_with_context.add(as_name)
             self.sheerka_methods[as_name] = SheerkaMethod(bound_method, has_side_effect)
+            if is_pipe_function:
+                self.pipe_functions.add(as_name)
 
-        setattr(self, bound_method.__name__, bound_method)
+        if not is_pipe_function:
+            setattr(self, bound_method.__name__, bound_method)
 
     def initialize(self, root_folder: str = None, **kwargs):
         """
@@ -655,6 +665,10 @@ class Sheerka(Concept):
         if obj.body is NotInit:
             return obj
 
+        if obj.key in BuiltinErrors:
+            # KSI 2021-04-20 # errors should be returned as soon as they are detected
+            return obj
+
         if reduce_simple_list and (isinstance(obj.body, list) or isinstance(obj.body, set)) and len(obj.body) == 1:
             body_to_use = obj.body[0]
         else:
@@ -673,39 +687,15 @@ class Sheerka(Concept):
 
         return (self.objvalue(obj) for obj in objs.body)
 
-    def get_errors(self, obj, **kwargs):
+    def get_errors(self, context, obj, **kwargs):
         """
         Browse obj, looking for error
+        :param context:
         :param obj:
         :param kwargs: if defined, specialize the error
         :return:
         """
 
-        def filter_by_type(x, name):
-            if isinstance(x, Concept):
-                return x.name == name
-            else:
-                return type(x).__name__ == name
-
-        def filter_by_attribute(x, attr_name, attr_value):
-            if hasattr(x, "as_bag"):
-                try:
-                    return x.as_bag()[attr_name] == attr_value
-                except KeyError:
-                    return False
-            else:
-                try:
-                    return getattr(x, attr_name) == attr_value
-                except AttributeError:
-                    return False
-
-        def and_filter(x, cond):
-            for c in cond:
-                if not c(x):
-                    return False
-
-            return True
-
         def is_error(_obj):
             if isinstance(_obj, ErrorObj):
                 return True
@@ -715,29 +705,6 @@ class Sheerka(Concept):
 
             return False
 
-        def filter_objects(_objects):
-            if kwargs:
-                cond = []
-                for k, v in kwargs.items():
-                    if k == "__type":
-                        expected_type = v
-                        cond.append(lambda x: filter_by_type(x, expected_type))
-                    else:
-                        attr_name = k
-                        expect_value = v
-                        cond.append(lambda x: filter_by_attribute(x, attr_name, expect_value))
-
-                if len(cond) > 1:
-                    copy_of_conditions = cond.copy()
-                    full_cond = lambda x: and_filter(x, copy_of_conditions)
-
-                else:
-                    full_cond = cond[0]
-
-                return [o for o in _objects if full_cond(o)]
-
-            return _objects
-
         def inner_get_errors(_obj):
             if self.isinstance(_obj, BuiltinConcepts.RETURN_VALUE) and _obj.status:
                 return []
@@ -748,6 +715,8 @@ class Sheerka(Concept):
             if is_error(_obj):
                 if isinstance(_obj, Concept) and _obj.body not in (NotInit, None):
                     return [_obj] + inner_get_errors(_obj.body)
+                if isinstance(_obj, ErrorObj) and hasattr(_obj, "get_error"):
+                    return [_obj] + inner_get_errors(_obj.get_error())
                 else:
                     return [_obj]
 
@@ -757,10 +726,10 @@ class Sheerka(Concept):
             return []
 
         errors = inner_get_errors(obj)
-        return filter_objects([e for e in errors])
+        return self.filter_objects(context, [e for e in errors], **kwargs)
 
-    def has_error(self, obj, **kwargs):
-        errors = self.get_errors(obj, **kwargs)
+    def has_error(self, context, obj, **kwargs):
+        errors = self.get_errors(context, obj, **kwargs)
         return len(errors) > 0
 
     def get_evaluator_name(self, name):
@@ -797,13 +766,6 @@ class Sheerka(Concept):
 
         return bool(obj)
 
-    @staticmethod
-    def is_error(obj):
-        """
-        opposite of is_success
-        """
-        return not Sheerka.is_success(obj)
-
     @staticmethod
     def is_known(obj):
         if not isinstance(obj, Concept):
@@ -844,7 +806,7 @@ class Sheerka(Concept):
         if isinstance(obj, Concept) and obj.id == self.id:
             return True
 
-        from evaluators.PythonEvaluator import Expando
+        from sheerkapython.python_wrapper import Expando
         if isinstance(obj, Expando) and obj.get_name() == "sheerka":
             return True