[fpc-pascal] Checking if a TStringList already exists

[Michael Van Canneyt]

On Tue, 21 May 2019, Graeme Geldenhuys wrote:

> On 20/05/2019 11:01 pm, Giuliano Colla wrote:
>> In some rare case when dealing with complex objects you might need 
>> FreeThenNil() in place of FreeAndNil().
>
> As far as I'm concerned, that is such a broken concept! The developer
> already has the burden to free any memory that he/she allocates. With
> what you are saying, it is now expected from the developer to look at
> all source code, flip and coin to decide how complex it is (that will
> vary between developers) and then decide which Free(Then|And)Nil()
> function to call!?  That should really be left up to the compiler and
> should be of no concern to the developer.
>
> Or there is a much simpler answer - the code the developer is working on
> is severely broken and needs some refactoring and decoupling of
> dependencies.

I'm with Graeme on this one.

FreeThenNil should never be necessary. 
FreeAndNil() should be enough for all circumstances.

Michael.