[swift5] Refactor some codes

[funzin]

Refactor some swift5 codes

• Use compactMap: ed52f32
• Remove as Any cast: a098063
• Remove unused array: a62aa84

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[funzin]

@4brunu
Please review it when you have time.

[4brunu]

@funzin Hey, thanks for creating this PR.
It's a nice improvement.
Looks good to me 👍
Thanks