14 lines
597 B
Markdown
14 lines
597 B
Markdown
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# Tune: unnecessary recursion
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Look for:
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- a recursive function that recomputes the same subproblem: memoize it or
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turn it into a loop;
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- recursion that only walks a list or a fixed depth: a loop;
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- a tree walk that visits or reads the same node more than once;
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- depth that grows with the input (stack limits, Python's 1000 frames);
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- recursive tool calls: a make target calling make, a role or playbook
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including itself, a script re-invoking itself per item.
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Count the calls first (a profiler's call graph, cProfile's `ncalls`, log
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lines); recursion that is bounded, rare and cheap stays.
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