Reimplemented explain feature

src/core/sheerka/Sheerka.py

@@ -83,6 +83,7 @@ class Sheerka(Concept):
             "test": self.test,
             "test_using_context": self.test_using_context
         }
+        self.sheerka_pipeables = {}
 
     @property
     def resolved_concepts_by_first_keyword(self):
@@ -121,6 +122,15 @@ class Sheerka(Concept):
 
         setattr(self, as_name, bound_method)
 
+    def add_pipeable(self, func_name, function):
+        """
+        Adds a function that can bu used with pipe '|'
+        :param func_name:
+        :param function:
+        :return:
+        """
+        self.sheerka_pipeables[func_name] = function
+
     def initialize(self, root_folder: str = None, save_execution_context=True):
         """
         Starting Sheerka
@@ -360,8 +370,11 @@ class Sheerka(Concept):
             if self.cache_manager.is_dirty:
                 self.cache_manager.commit(execution_context)
 
-            if self.save_execution_context and self.load(self.name, "save_execution_context"):
-                self.sdp.save_result(execution_context)
+            try:
+                if self.save_execution_context and self.load(self.name, "save_execution_context"):
+                    self.sdp.save_result(execution_context)
+            except Exception as ex:
+                self.log.error(f"Failed to save execution context. Reason: {ex}")
 
         # # hack to save valid concept definition
         # if not self.during_restore:
@@ -760,6 +773,9 @@ class Sheerka(Concept):
         except IOError:
             pass
 
+    def get_last_execution(self):
+        return self._last_execution
+
     def test(self):
         return f"I have access to Sheerka !"
 
@@ -841,6 +857,28 @@ class Sheerka(Concept):
 
     @staticmethod
     def init_logging(debug, loggers):
+        def add_coloring_to_emit_ansi(fn):
+            # add methods we need to the class
+            def new(*args):
+                levelno = args[1].levelno
+                if levelno >= 50:
+                    color = '\x1b[31m'  # red
+                elif levelno >= 40:
+                    color = '\x1b[31m'  # red
+                elif levelno >= 30:
+                    color = '\x1b[33m'  # yellow
+                elif levelno >= 20:
+                    color = '\x1b[32m'  # green
+                elif levelno >= 10:
+                    color = '\x1b[35m'  # pink
+                else:
+                    color = '\x1b[0m'  # normal
+                args[1].msg = color + str(args[1].msg) + '\x1b[0m'  # normal
+                # print "after"
+                return fn(*args)
+
+            return new
+
         core.sheerka_logger.init_config(loggers)
         if debug:
             log_format = "%(asctime)s"
@@ -853,3 +891,6 @@ class Sheerka(Concept):
             log_level = logging.INFO
 
         logging.basicConfig(format=log_format, level=log_level, handlers=[console_handler])
+        logging.addLevelName(logging.ERROR, "\033[1;41m%s\033[1;0m" % logging.getLevelName(logging.ERROR))
+        # uncomment the following line to enable colors
+        #logging.StreamHandler.emit = add_coloring_to_emit_ansi(logging.StreamHandler.emit)