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Comment by apaprocki

14 hours ago

> > typedef struct { ... } String

> I avoid doing this. Just use `struct string { ... };'. It makes it clear what you're handling.

Well then imagine if Gtk made you write `struct GtkLabel`, etc. and you saw hundreds of `struct` on the screen taking up space in heavy UI code. Sometimes abstractions are worthwhile.

7 comments

apaprocki

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wavemode  12 hours ago

The main thing I dislike about typedefs is that you can't forward declare them.

If I know for sure I'm never going to need to do that then OK.

  • procaryote  11 hours ago

    How do you mean? You can at least do things like

    typedef struct foo foo;

    and somewhere else

    struct foo { … }

  • flohofwoe  6 hours ago

    The usual solution for this is:

        typedef struct bla_s { ... } bla_t;

    Now you have a struct named 'bla_s' and a type alias 'bla_t'. For the forward declaration you'd use 'bla_s'.

    Using the same name also works just fine, since structs and type aliases live in different namespaces:

        typedef struct bla_t { ... } bla_t;

    ...also before that topic comes up again: the _t postfix is not reserved in the C standard :)

    • apaprocki  3 hours ago

      Yes, using the same Gtk example, the way you’d forward declare GtkLabel without including gtklabel.h in your header would be:

          struct _GtkLabel;
    typedef struct _GtkLabel GtkLabel;
    // Use GtkLabel* in declarations

      1 reply →

    • warmwaffles  2 hours ago

      People getting hung up on `_t` usage being reserved for posix need to lighten up. I doubt they'll clash with my definitions and if does happen in the future, I'll change the typedef name.

lelanthran  11 hours ago

> Well then imagine if Gtk made you write `struct GtkLabel`, etc. and you saw hundreds of `struct` on the screen taking up space in heavy UI code. Sometimes abstractions are worthwhile.

TBH, in that case the GtkLabel (and, indeed, the entire widget hierarchy) should be opaque pointers anyway.

If you're not using a struct as an abstraction, then don't typedef it. If you are, then hide the damn fields.