OK, I'm more awake now. And I realized that this wouldn't work.

Suppose that we have 4 objects, the second one depends on the fourth, and there are no other dependencies. Then Perl will (does a quick test) compare the first to the second, the third to the fourth, the first to the third and the third to the second. Then conclude that they are all equivalent and will return the list in the original order.

Note that the second and fourth never got compared at all.

The moral of the story is that sort algorithms assume that comparison functions are well-behaved. Your comparison function isn't so it misbehaves.

In reply to Re^2: Partial sort for dependency graph by tilly
in thread Partial sort for dependency graph by throop

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