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Question: why one can not add type to _self on OOP static methods?

Question:why one can not add type to _self on OOP static methods?

nm 10234 Maple 2023
module object object-oriented-programming static
December 06 2023
2

I thought I was improving my code by adding ::type to all the _self in my OOP code. As this is one main advantage in programming in Maple, which is being able to attach types to all name and variables. Make code more robust.

But it turned out Maple is not very happy now and gives that drearded error

    Error, static procedure ... refers to non-static local or export ... in surrounding scope

Only place I found that adding ::type_name is to _self is allowed, is on the constructor signature.

But in no other method of the object module. local or export method, it does not matter. 

My question is, why is that?

So I went and removed all those _self::type_name and made it just _self to make Maple happy.

I also noticed this happes regardless of having kernelopts('assertlevel'=2): there or not.  Attached  is the worksheet.

Just tryting to understand the logic, that is all. 

This is using Maple 2023.2.1

> 

interface(version)

`Standard Worksheet Interface, Maple 2023.2, Windows 10, November 24 2023 Build ID 1762575`

> 

restart;

24100

> 

interface(warnlevel=4);
kernelopts('assertlevel'=2):

3

> 

A:=module()

  export module person()
   option object;
   local m_name::string;
   local m_age::integer;
   export ModuleCopy::static:=proc(_self::A:-person,proto::A:-person,name::string,age::integer,$)
          _self:-m_age := age;
          _self:-m_name:=name;
          NULL;
   end proc;
   export name::static:=proc(_self,$) m_name; end proc;
   export age::static:=proc(_self,$) m_age; end proc;
 end module;

export  module young_person()
   option object;
   local m_person::A:-person;
   export ModuleCopy::static:=proc(_self::A:-young_person,proto::A:-young_person,p::A:-person,$)
          _self:-m_person := p;     
          _self:-process_it();    
   end proc;
   local process_it::static:=proc(_self,$)
         print(m_person:-name());
         print(m_person:-age());
   end proc;

   #to fix the problem, check _self::A... to just _self,  then no error!
   export process_it_from_outside::static:=proc(_self::A:-young_person,$)
         print(m_person:-name());
         print(m_person:-age());
   end proc;

end module;

end module;

_m2782933017664

> 

o:=Object(A:-person,"me",99);

module person () local m_name::string, m_age::integer; option object; end module

> 

p:=Object(A:-young_person,o);
> 

 

Error, static procedure `young_person:-process_it_from_outside` refers to non-static local or export `young_person:-m_person::A:-person` in surrounding scope

> 

 


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