Clarify how derangements treats duplicate inputs#1069
Merged
bbayles merged 1 commit intomore-itertools:masterfrom Sep 1, 2025
Merged
Clarify how derangements treats duplicate inputs#1069bbayles merged 1 commit intomore-itertools:masterfrom
bbayles merged 1 commit intomore-itertools:masterfrom
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With duplicate inputs, the output of derangements doesn't make sense. Given
['Alice', 'Bob', 'Bob'], the output includes('Bob', 'Bob', 'Alice')which appears to violate the fixed-point invariant by leaving'Bob'in the middle position.Add text to explain what derangements is doing, a plausible rationale for its behavior, and practical advice for avoiding the issue.