Added empty string parser

core/builtin_concepts.py

@@ -25,6 +25,7 @@ class BuiltinConcepts(Enum):
     PARSING = 16  # activated during the parsing. It contains the text to parse
     AFTER_PARSING = 17  # activated when the parsing process seems to be finished
     CONCEPT_ALREADY_DEFINED = 18  # when you try to add the same concept twice
+    NOP = 19  # no operation concept. Does nothing
 
 
 """

core/sheerka.py

@@ -208,7 +208,8 @@ class Sheerka(Concept):
         return result
 
     def process(self, context, return_values, contextual_concepts=None):
-        log.debug("Evaluating parsing result.")
+        contextual_concepts_values = [c.value for c in contextual_concepts] if contextual_concepts else []
+        log.debug(f"Processing parsing result. context concept={contextual_concepts_values}")
 
         # return_values must be a list
         if not isinstance(return_values, list):
@@ -317,8 +318,12 @@ class Sheerka(Concept):
         """
         for part_key in ConceptParts:
             source = getattr(concept, part_key.value)
-            if source is None or source == "":
+            if source is None or not isinstance(source, str) or source == "":
+
+                # the only sources that I am sure to parse are strings
+                # I refuse empty strings for performance, I don't want to handle useless NOPConcepts
                 continue
+
             ret_val = self.expect_one(context, self.parse(context, source))
             concept.codes[part_key] = ret_val