Added empty string parser

parsers/EmptyStringParser.py

@@ -0,0 +1,26 @@
+from core.builtin_concepts import BuiltinConcepts
+from parsers.BaseParser import BaseParser
+import logging
+
+log = logging.getLogger(__name__)
+
+
+class EmptyStringParser(BaseParser):
+    """
+    To parse empty or blank strings
+    """
+
+    def __init__(self):
+        BaseParser.__init__(self, "NullParser")
+
+    def parse(self, context, text):
+        sheerka = context.sheerka
+
+        if isinstance(text, str) and text.strip() == "" or \
+            isinstance(text, list) and text == [] or \
+            text is None:
+            log.debug(f"Recognized '{text}' as BuiltinConcepts.NOP.")
+            return sheerka.ret(self.name, True, sheerka.new(BuiltinConcepts.NOP))
+
+        log.debug(f"Failed to recognize '{text}'")
+        return sheerka.ret(self.name, False, sheerka.new(BuiltinConcepts.NOT_FOR_ME))

parsers/ExactConceptParser.py

@@ -28,7 +28,7 @@ class ExactConceptParser(BaseParser):
         sheerka = context.sheerka
         words = self.get_words(text)
         if len(words) > self.MAX_WORDS_SIZE:
-            return ReturnValueConcept(self.name, False, sheerka.new(BuiltinConcepts.CONCEPT_TOO_LONG, obj=text))
+            return sheerka.ret(self.name, False, sheerka.new(BuiltinConcepts.CONCEPT_TOO_LONG, obj=text))
 
         recognized = False
         for combination in self.combinations(words):
@@ -53,7 +53,7 @@ class ExactConceptParser(BaseParser):
             return res
 
         log.debug(f"Failed to recognize {words}")
-        return ReturnValueConcept(self.name, False, sheerka.new(BuiltinConcepts.UNKNOWN_CONCEPT, obj=text))
+        return sheerka.ret(self.name, False, sheerka.new(BuiltinConcepts.UNKNOWN_CONCEPT, obj=text))
 
     @staticmethod
     def get_words(text):