gh-somegeekintn-SimDirs/SimDirs/Support.swift

//
//  Support.swift
//  SimDirs
//
//  Created by Casey Fleser on 4/30/16.
//  Copyright © 2016 Quiet Spark. All rights reserved.
//
//	Assorted convenience extensions

import Foundation

extension Array {
	mutating func match(_ predicate: (Element) -> Bool, orMake: () -> Element) -> Element {
		let element	: Element
		
		if let match = self.first(where: predicate) {
			element = match
		}
		else {
			element = orMake()
			self.append(element)
		}
		
		return element
	}
}

extension Collection {
    subscript (safe index: Index) -> Iterator.Element? {
        return indices.contains(index) ? self[index] : nil
    }
}

extension String {
    var validPath	: Bool { return FileManager.default.fileExists(atPath: self) }
}

extension NSURL {
    var validPath	: Bool { return self.path.map { FileManager.default.fileExists(atPath: $0) } ?? false  }
}

extension PropertyListSerialization {
	class func propertyListWithURL(_ url: URL) -> [String : AnyObject]? {
        guard let plistData	= try? Data(contentsOf: url) else { return nil }
		let plist			: [String : AnyObject]?

		do {
            plist = try PropertyListSerialization.propertyList(from: plistData, options: [], format: nil) as? [String : AnyObject]
		} catch {
			plist = nil
		}
		
		return plist
	}
}