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permute 

        # OptionParser.permute

(from ruby core)
---
    permute(*argv, into: nil)

---

Parses command line arguments `argv` in permutation mode and returns
list of non-option arguments. When optional `into` keyword argument is
provided, the parsed option values are stored there via `[]=` method (so
it can be Hash, or OpenStruct, or other similar object).

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