Help with basic OO question

[Former Member]

Right!

I know that '->' is for calling a method from a class.

I also know that '=>' is used calling a static method (whatever that is?).

But what on earth is '?=' used for???

Anyone got any ideas...

Thanking you kindly

[RichHeilman]

?= is use for casting. Narrowing and widening.

You will usually see this inside of a catch/endcatch.

    catch system-exceptions move_cast_error = 1.
      r_checking ?= r_account.
    call method r_account->show_balance.
    endcatch.

Check out this post.

Regards,

Rich Heilman

[Former Member]

oh right that's it, casting...

That something to do with what is inherited from superclasses...

Thansk for the memory jog!