Flatten file directories (fixes #159)

Sources/SectionBy.swift

@@ -0,0 +1,76 @@
+//
+//  SectionBy.swift
+//  CoreStore
+//
+//  Copyright © 2015 John Rommel Estropia
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy
+//  of this software and associated documentation files (the "Software"), to deal
+//  in the Software without restriction, including without limitation the rights
+//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//  copies of the Software, and to permit persons to whom the Software is
+//  furnished to do so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+//
+
+import Foundation
+import CoreData
+
+
+#if os(iOS) || os(watchOS) || os(tvOS)
+
+// MARK: - SectionBy
+
+/**
+ The `SectionBy` clause indicates the key path to use to group the `ListMonitor` objects into sections. An optional closure can also be provided to transform the value into an appropriate section name:
+ ```
+ let monitor = CoreStore.monitorSectionedList(
+     From<MyPersonEntity>(),
+     SectionBy("age") { "Age \($0)" },
+     OrderBy(.ascending("lastName"))
+ )
+ ```
+ */
+public struct SectionBy {
+    
+    /**
+     Initializes a `SectionBy` clause with the key path to use to group `ListMonitor` objects into sections
+     
+     - parameter sectionKeyPath: the key path to use to group the objects into sections
+     */
+    public init(_ sectionKeyPath: KeyPath) {
+        
+        self.init(sectionKeyPath, { $0 })
+    }
+    
+    /**
+     Initializes a `SectionBy` clause with the key path to use to group `ListMonitor` objects into sections, and a closure to transform the value for the key path to an appropriate section name
+     
+     - Important: Some utilities (such as `ListMonitor`s) may keep `SectionBy`s in memory and may thus introduce retain cycles if reference captures are not handled properly.
+     - parameter sectionKeyPath: the key path to use to group the objects into sections
+     - parameter sectionIndexTransformer: a closure to transform the value for the key path to an appropriate section name
+     */
+    public init(_ sectionKeyPath: KeyPath, _ sectionIndexTransformer: @escaping (_ sectionName: String?) -> String?) {
+        
+        self.sectionKeyPath = sectionKeyPath
+        self.sectionIndexTransformer = sectionIndexTransformer
+    }
+    
+    
+    // MARK: Internal
+    
+    internal let sectionKeyPath: KeyPath
+    internal let sectionIndexTransformer: (_ sectionName: String?) -> String?
+}
+
+#endif