Is the Abstract keyword needed to make a method abstract?

Is this correct Matlab syntax

classdef MyClass
    methods
        outarg = my_method( this, inarg );
    end
end

R2018b accepts it. Assuming this class definition is correct

• is MyClass abstract?
• is the method, my_method, abstract?

meta.class reports that .Abstract==false for both.

[per isakson]

Addendum: "Run in R2021a" can't execute these lines in the question, since the class definition causes an error

meta_class = meta.class.fromName( 'MyClass' );
meta_class.Abstract

ans = logical
   0

meta_class.MethodList(1).Name

ans = 'my_method'

meta_class.MethodList(1).Abstract

ans = logical
   0

Answer 1

[Steven Lord]

That is valid syntax, but not for making my_method an Abstract method. What you've written tells MATLAB that my_method is implemented in a separate file, not in the classdef file for MyClass.

See this documentation page for more information on how to declare a method as Abstract.

classdef MyClass
    methods (Abstract)
        outarg = my_method( this, inarg );
    end
end

[per isakson]

@Steven Lord, thank you for the answer. I had forgotten (I never use separate files).

However, that means that MyClass.m needs to be in a class folder named, @MyClass.