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Development Team Blog

  1. Address and Pointer, what's up with that?

    by , 1-Apr-2010 at 08:00 AM (Development Team Blog)
    If you've been a VDF developer for a while you've undoubtedly come across [I]Pointer[/I], but what about the [I]Address[/I] type? Isn't that just redundant?

    [I]Pointer[/I] has been around seemingly forever, but you may or may not know that [I]Pointer[/I] is not a real data type in its own right. If you type [I]Pointer[/I] in the Visual DataFlex Studio editor and hover your mouse cursor over the word, you'll see a tooltip that says "Alias type Pointer Integer". So even though ...
  2. Byref Explained

    by , 12-Oct-2009 at 08:00 AM (Development Team Blog)
    [I]Pointer[/I], [I]byref[/I], [I]AddressOf()[/I], what's the difference between [I]byref[/I] and [I]Pointer[/I] anyway? If you know C++ you might say that by-reference is semantically very similar to a pointer but with different syntax. In Visual DataFlex, [I]byref[/I] and [I]pointer[/I] are actually used for different purposes.

    This is best illustrated with [I]String[/I], consider the following code:

    Use DfAllEnt.pkg

    Procedure Foo String ...