- how to call a method of an object

- input of / * - + should be updated with it the parents return type if dropped onto some object.

? list of types (variable and attribute) should be dynamic and also include names of Entities and Worlds

OK do not allow to have twice the same event for a given class

OK- Checks    
    OK- do not allow two attributes with the same name in the same class
    OK- update variable usage if declaration is moved away (maybe out of block!!)
    OK- do not allow two variables with the same name in the same block