lib/dry/monads/errors.rb in dry-monads-1.2.0 vs lib/dry/monads/errors.rb in dry-monads-1.3.0

@@ -11,7 +11,17 @@
     class InvalidFailureTypeError < StandardError
       def initialize(failure)
         super("Cannot create Failure from #{ failure.inspect }, it doesn't meet the constraints")
       end
     end
+
+    # Improper use of None
+    class ConstructorNotAppliedError < NoMethodError
+      def initialize(method_name, constructor_name)
+        super(
+          "For calling .#{method_name} on #{constructor_name}() build a value "\
+          "by appending parens: #{constructor_name}()"
+        )
+      end
+    end
   end
 end