[fpc-pascal] Dynamic arrays, yet another pitfall

[Michael Van Canneyt]

On Sun, 16 Feb 2014, Jürgen Hestermann wrote:

> Am 2014-02-16 13:47, schrieb Florian Klämpfl:
>> setlength does not behave freaky but its behaviour is well designed. The
>> reason why setlength does a deep copy is simple: multithreading. If
>> setlength had no deep copy semantics, it would need locking of the whole
>> array data, not only locked access to the ref. counter.
>
> There may be good reasons for doing it the way it has been done.
> But for a programmer (who has not written the compiler) this behaviour is 
> totaly unexpected.
> When using unknown features of a programming language for the first time
> then the documentaion should tell all aspects in detail and describe the 
> exact behaviour.

It does exactly that, it says:
1) No COW
and I added:
2) SetLength enforces unique ref. count.

Michael.
>
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