TIL Rule of Three in Refactoring

POSTED ON: Dec 28, 2021

The rule was popularized by Martin Fowler in Refactoring[1] and attributed to Don Roberts.

It states that two instances of similar code do not require refactoring,
But when similar code is used three times, it should be extracted into a new procedure.

Overall, wait until you see the duplication happening a third time before you introduce your abstraction.

With more occurrences, it will be easier to find the commonalities to extract.

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