change args argument to create method to be hash

was array and didn’t carry types and names

lib/soml/compiler/name_expression.rb

@@ -38,7 +38,7 @@ module Soml
             return ret
           end
         end
-        raise "must define variable #{name} before using it"
+        raise "must define variable '#{name}' before using it"
       end
 
   end #module