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Message:

Collections framework: is sort() always stable?

Posted by Steven Tolkin on April 24, 2000 at 5:45 PM

Is there a guarantee that sort() will be stable?
Suppose I implement a faster sort algorithm that is not stable.
For example one can sort integers in log log n (sic) time.
Am I "allowed" to use a non-stable sort for sort()?
If so code that depended on sort being stable will likely break.
Perhaps we should encourage naming this nonstableSort() as a
precaution. (This kind of guarantee is very hard to express,
even if "programming by contract" is later added to Java.
Does Eiffel have a solution to this? Or must we rely on
conventions, e.g. names for methods, etc.)