NSRangeをRangeに変換しようとすると、生のHTTPレスポンスを解析しようとしていますが、範囲が正しくありません。NSRegularExpressionを使用した奇妙な文字列範囲の動作
public extension NSRange {
public func toStringRange(_ str: String) -> Range<String.Index>? {
guard str.characters.count >= length - location && location < str.characters.count else { return nil }
let fromIdx = str.characters.index(str.startIndex, offsetBy: self.location)
print("from: \(self.location) = \(fromIdx)")
let toIdx = str.characters.index(fromIdx, offsetBy: self.length)
return fromIdx..<toIdx
}
}
let responseString = "HTTP/1.0 200 OK\r\nContent-Length: 193\r\nContent-Type: application/json\r\n"
let responseRange = NSRange(location: 0, length: responseString.characters.count)
let responseRegex = try! NSRegularExpression(pattern: "^(HTTP/1.\\d) (\\d+) (.*?\r\n)(.*)", options: [.anchorsMatchLines])
guard let matchResult = responseRegex.firstMatch(in: responseString, options: [], range: responseRange),
matchResult.numberOfRanges == 5,
let versionRange = matchResult.rangeAt(1).toStringRange(responseString),
let statusRange = matchResult.rangeAt(2).toStringRange(responseString),
let headersRange = matchResult.rangeAt(4).toStringRange(responseString)
else { fatalError() }
)(toStringRangeの印刷出力
from: 0 = Index(_base: Swift.String.UnicodeScalarView.Index(_position: 0), _countUTF16: 1)
from: 9 = Index(_base: Swift.String.UnicodeScalarView.Index(_position: 9), _countUTF16: 1)
from: 17 = Index(_base: Swift.String.UnicodeScalarView.Index(_position: 18), _countUTF16: 1)
なぜ3 toStringRange()呼び出しではなく、18で始まる文字列の範囲を返してある:ここで遊び場から関連するコードであります17の? NSRange
からRange<String.Index>
へ