Gwendal Roué groue

This blog post shows how Swift protocols can help using CoreData: http://martiancraft.com/blog/2015/07/objective-c-swift-core-data/

Following this advice, I have tried this technique, with success, but with a request for improvement.

Below you will find a bare minimal view of the API I'm working on. Notice the not nice Person.self in the line db.fetchAll(Person.self, "SELECT * FROM persons"). I want to improve that, and the linked blog post was a great deal of inspiration.

// Library
class RowModel {} // Equivalent of NSManagedObject in Core Data
class Database {

Hello,

I'm working on a class that synthesizes its own property accessors when the user subclasses it, and declares properties @dynamic.

That class is part of the GRMustache library, and is documented in https://github.com/groue/GRMustache/blob/master/Guides/view_model.md

Today, the current implementation works, and is robust. The end user has a very simple API - he just has to declare dynamic properties in order to be granted with the features he needs. I'm quite happy of that.

Documentation of filters: https://github.com/groue/GRMustache/blob/master/Guides/filters.md

	// Library code
	class Model { }
	protocol Fetchable {
	typealias FetchableType = Self
	static func fetchAll(sql: String) -> [FetchableType]
	}

	extension Fetchable where Self : Model, FetchableType == Self {
	static func fetchAll(sql: String) -> [FetchableType] {
	return [] // bare minimal, for demonstration purpose

	// Library code
	class Model { }
	protocol Fetchable {
	typealias FetchableType
	static func fetchAll(sql: String) -> [FetchableType]
	}

	extension Fetchable where Self : Model, FetchableType == Self {
	static func fetchAll(sql: String) -> [FetchableType] {
	return [] // bare minimal, for demonstration purpose

	import Foundation

	// A function declared as rethrows that synchronously executes a throwing
	// block in a dispatch_queue.
	//
	// Based on Ransak's answer to https://forums.developer.apple.com/message/19685
	func perform_sync(queue: dispatch_queue_t, block: () throws -> Void) rethrows {
	func impl(queue: dispatch_queue_t, block: () throws -> Void, block2:((ErrorType) throws -> ()) ) rethrows {
	var blockError: ErrorType? = nil
	dispatch_sync(queue) {

	import Mustache

	// Wrap the result in a section, and the key `cycleKey` will enumerate and cycle
	// around boxes, one after the other.
	func cyclingBox(key cycleKey: String, #boxes: [MustacheBox]) -> MustacheBox {
	var index = 0
	return Box { (key: String) in
	if key == cycleKey {
	let box = boxes[index]
	index = (index + 1) % boxes.count

	import Foundation

	// =============================================================================
	// Box

	// The Box
	struct Box {
	let value: Any
	let walk: () -> ()
	}

	#import "GRMustache.h"

	NSString *templateString = @"{{# repeat(Red) }}<img src=\"img/red.png\">{{/ repeat(Red) }}}";
	GRMustacheTemplate *template = [GRMustacheTemplate templateFromString:templateString error:NULL];

	id obj = @{
	@"Red": @10,
	@"repeat": [GRMustacheFilter filterWithBlock:^id(NSNumber *number) {
	NSInteger count = [number integerValue];
	return [GRMustache renderingObjectWithBlock:^NSString (GRMustacheTag tag, GRMustacheContext context, BOOL HTMLSafe, NSError __autoreleasing error) {