[fpc-pascal] Changing var to out in rtl code

Michael Van Canneyt michael at freepascal.org
Sun Nov 21 19:22:20 CET 2010

On Sun, 21 Nov 2010, Max Vlasov wrote:

> Hi,
> I'm one of those developers who takes hints and warnings seriously and I must say at least once a week it helps me find a bugs even before running the
> program. So when I got a warning about some uninitialized variable passed by reference (Delphi 5 is ok with such variable being uninitialized), I thought
> what I should do to fix this, and the best solution for this is changing the declaration from "var " to to "out " (CMIIW).
> But is it possible to do the same (partially, gradually or in any other way) for the "legacy" code that keeps the interface compatibility with Delphi.
> For example TStrignList.Find(const S: string; var Index: Integer): Boolean; declares "var " so my existing fragments expecting just an result from this
> call, got "Hint: Local variable "Index" does not seem to be initialized" warning. But looking at the implementation details it seems it is safe to change
> "var Index" to "out Index" and possibly it is also safe for any delphi/lazarus code calling this method

For this particular instance, I changed the code. (rev 16395)
But in general, one must be careful with changing such things.


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