Slide 33
Slide 33 text
Stdlib
ରίʔυ: https://
github.com/kateinoigakukun/
swift-lto-benchmark/blob/
master/Example/
SwiftStdlibExample.swift
let alphabet = "abcdefghijklmnopqrstuvwxyz"
/// All edits that are one edit away from `word`
func edits(_ word: String) -> Set {
let splits = word.indices.map {
(String(word[..<$0]), String(word[$0...]))
}
var result: Array = []
for (left, right) in splits {
// drop a character
result.append(left + right.dropFirst())
// transpose two characters
if let fst = right.first {
let drop1 = right.dropFirst()
if let snd = drop1.first {
result.append(left + [snd,fst] + drop1.dropFirst())
}
}
// replace each character with another
for letter in alphabet {
result.append(left + [letter] + right.dropFirst())
}
// insert rogue characters
for letter in alphabet {
result.append(left + [letter] + right)
}
}
// have to map back to strings right at the end
return Set(result)
}
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