Namespace lazy sequence under CSVDecoder.LazySequence

Author: josh

sources/declarative/decodable/Decoder.swift

@@ -64,18 +64,18 @@ extension CSVDecoder {
     /// Returns a sequence for decoding each row from a CSV file (given as a `Data` blob).
     /// - parameter data: The data blob representing a CSV file.
     /// - throws: `CSVError<CSVReader>` exclusively.
-    open func lazy(from data: Data) throws -> CSVDecoderSequence {
+    open func lazy(from data: Data) throws -> LazySequence {
         let reader = try CSVReader(input: data, configuration: self.configuration.readerConfiguration)
         let source = ShadowDecoder.Source(reader: reader, configuration: self.configuration, userInfo: self.userInfo)
-        return CSVDecoderSequence(source: source)
+        return LazySequence(source: source)
     }
 
     /// Returns a sequence for decoding each row from a CSV file (being pointed by `url`).
     /// - parameter url: The URL pointing to the file to decode.
     /// - throws: `CSVError<CSVReader>` exclusively.
-    open func lazy(from url: URL) throws -> CSVDecoderSequence {
+    open func lazy(from url: URL) throws -> LazySequence {
         let reader = try CSVReader(input: url, configuration: self.configuration.readerConfiguration)
         let source = ShadowDecoder.Source(reader: reader, configuration: self.configuration, userInfo: self.userInfo)
-        return CSVDecoderSequence(source: source)
+        return LazySequence(source: source)
     }
 }

sources/declarative/decodable/DecoderSequence.swift

@@ -1,31 +1,37 @@
-open class CSVDecoderSequence: IteratorProtocol, Sequence {
-    private let source: ShadowDecoder.Source
-    private var currentIndex: Int = 0
+extension CSVDecoder {
+    public struct LazySequence: IteratorProtocol, Sequence {
+        private let source: ShadowDecoder.Source
+        private var currentIndex: Int = 0
 
-    init(source: ShadowDecoder.Source) {
-        self.source = source
-    }
+        init(source: ShadowDecoder.Source) {
+            self.source = source
+        }
+
+        /// Advances to the next row and returns a `CSVRowDecoder`, or `nil` if no next row exists.
+        public mutating func next() -> Row? {
+            guard !self.source.isRowAtEnd(index: self.currentIndex) else {
+                return nil
+            }
 
-    /// Advances to the next row and returns a `CSVRowDecoder`, or `nil` if no next row exists.
-    public func next() -> CSVRowDecoder? {
-        guard !self.source.isRowAtEnd(index: self.currentIndex) else {
-            return nil
+            defer { self.currentIndex += 1 }
+            let decoder = ShadowDecoder(source: source, codingPath: [IndexKey(self.currentIndex)])
+            return Row(decoder: decoder)
         }
 
-        defer { self.currentIndex += 1 }
-        let decoder = ShadowDecoder(source: source, codingPath: [IndexKey(self.currentIndex)])
-        return CSVRowDecoder(decoder: decoder)
-    }
-}
+        public struct Row {
+            /// The representation of the decoding process point-in-time.
+            private let decoder: ShadowDecoder
 
-public struct CSVRowDecoder {
-    /// The representation of the decoding process point-in-time.
-    let decoder: ShadowDecoder
+            fileprivate init(decoder: ShadowDecoder) {
+                self.decoder = decoder
+            }
 
-    /// Returns a value of the type you specify, decoded from CSV row.
-    /// - parameter type: The type of the value to decode from the supplied file.
-    /// - throws: `DecodingError`, or `CSVError<CSVReader>`, or the error raised by your custom types.
-    public func decode<T:Decodable>(_ type: T.Type) throws -> T {
-        return try T(from: decoder)
+            /// Returns a value of the type you specify, decoded from CSV row.
+            /// - parameter type: The type of the value to decode from the supplied file.
+            /// - throws: `DecodingError`, or `CSVError<CSVReader>`, or the error raised by your custom types.
+            public func decode<T:Decodable>(_ type: T.Type) throws -> T {
+                return try T(from: decoder)
+            }
+        }
     }
 }