This is a story about how I gradually fell in love with composition
  • dragontamer@lemmy.worldEnglish
    73·
    2 years ago

    You’re not describing composition.

    Go Files do not “hasa reader”. You don’t do file.reader.read(), you just do file.read(), that’s inheritance as file has inherited the read() method.

    • colonial@lemmy.worldEnglish
      81·
      2 years ago

      You’re confusing polymorphism for inheritance. read is a method on an interface that File implements - it is not inherited from a base class. You can use that File directly, or wherever a Reader interface (or whatever the name is, idk I don’t really do Go) is expected.

    • orangeboats@lemmy.worldEnglish
      5·
      2 years ago

      Composition do not necessitate the creation of a new field like x.reader or x.writer, what are you on?

        • platypus_plumba@lemmy.worldEnglish
          11·
          2 years ago

          Man, I honestly have no idea why they are downvoting you. Composition literally means taking common behavior and placing it in external objects behind interfaces using a has-a relationship.

          No idea why they are denying this. Inheritance vs composition is the same as “is-a” vs “has-a”. In composition re usability isn’t done via inheritance but code encapsulation.

          Saying that in Go objects can implement many interfaces is the Interface Segregation principle from SOLID. Basically having small interfaces instead of a big interface with methods that may not be implemented by all implementors.