Fixed #101 : Implement PLURIAL

Fixed #103 : Implement PlurialNodeParser
Fixed #104 : Implement dynamic concept
Fixed #107 : PrepareEvalxxxEvaluator: context hints are lost on a second evaluation

src/core/sheerka/Sheerka.py

@@ -546,11 +546,12 @@ class Sheerka(Concept):
 
         return new_instances(concept, recognized_by, is_instance, is_evaluated) if return_new else concept
 
-    def new(self, concept_key, **kwargs):
+    def new(self, concept_key, allow_dynamic=False, **kwargs):
         """
         Returns an instance of a new concept
         When the concept is supposed to be unique, returns the same instance
         :param concept_key:
+        :param allow_dynamic:
         :param kwargs:
         :return:
         """
@@ -561,7 +562,8 @@ class Sheerka(Concept):
         else:
             concept_id = None
 
-        template = self.get_by_id(concept_id) if not concept_key else self.get_by_key(concept_key, concept_id)
+        template = self.get_by_id(concept_id, allow_dynamic) if not concept_key else \
+            self.get_by_key(concept_key, concept_id)
 
         # manage concept not found
         if self.isinstance(template, BuiltinConcepts.UNKNOWN_CONCEPT) and \
@@ -610,6 +612,43 @@ class Sheerka(Concept):
         concept.get_hints().is_evaluated = True  # because we have manually set the variables
         return concept
 
+    def new_dynamic(self, concept_or_key, id_suffix, name=None, props=None, attrs=None):
+        """
+        Create a dynamic concept with the given props and attrs
+        A dynamic concept is a concept that is not declared by 'def concept' but can be deduced from another one
+        ex: 'boys' can be deduced from 'boy' (given that it's its plural).
+        dynamic concept are a convenient way not to define all possible concepts
+        :param concept_or_key:
+        :param id_suffix:
+        :param name: new name and key for the concept
+        :param props:
+        :param attrs:
+        :return:
+        """
+        if not isinstance(concept_or_key, Concept):
+            concept = self.fast_resolve(concept_or_key, return_new=True)
+        else:
+            concept = Concept().update_from(concept_or_key, update_value=False)
+
+        if hasattr(concept, "__iter__"):
+            # TODO: replace exception by the Concept TOO_MANY_SUCCESS and make sure that it is correctly manage
+            raise NotImplementedError("Too many concepts")
+
+        concept.get_metadata().id = f"{concept.id}-{id_suffix}"
+        if name:
+            concept.get_metadata().name = name
+            concept.get_metadata().key = name
+
+        if props:
+            for k, v in props.items():
+                concept.set_prop(k, v)
+
+        if attrs:
+            for k, v in attrs.items():
+                concept.set_value(k, v)
+
+        return concept
+
     def push_ontology(self, context, name, cache_only=False):
 
         try: