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tomisacat/filter_digits.swift

Last active April 6, 2017 14:39
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simple illustration of `flatMap` and `reduce` to filter digits from string
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filter_digits.swift
let s = "fdsf6fdsf7dsf7s7sdf789sdff9s8fs8df98dfsdsd5fsf"
let r = s.characters.flatMap { Int(String($0)) != nil ? nil : $0 }.reduce("") { $0 + String($1) }
Swift.print(r)
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It's inefficient and you should use filter with regular expression.

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