I can define and eval BNF definitions

evaluators/ConceptEvaluator.py

@@ -4,12 +4,16 @@ from core.concept import Concept, ConceptParts
 from evaluators.BaseEvaluator import OneReturnValueEvaluator
 import logging
 
-from parsers.BaseParser import BaseParser
-
 log = logging.getLogger(__name__)
 
 
 class ConceptEvaluator(OneReturnValueEvaluator):
+    """
+    The concept evaluatuor is the main class that know what to do with a concept
+    It verifies the PRE
+    If ok, can execute or not the BODY
+    Then checks the POST conditions
+    """
     NAME = "Concept"
     evaluation_steps = [BuiltinConcepts.EVALUATION, BuiltinConcepts.AFTER_EVALUATION]