Eric Kunz ericjkunz

System Design Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

User cases (description of sequences of events that, taken together, lead to a system doing something useful)
- Who is going to use it?
- How are they going to use it?

	/// Withable is a simple protocol to make constructing
	/// and modifying objects with multiple properties
	/// more pleasant (functional, chainable, point-free)
	public protocol Withable {
	init()
	}

	public extension Withable {
	/// Construct a new instance, setting an arbitrary subset of properties
	init(with config: (inout Self) -> Void) {

	import Foundation

	extension UnicodeScalar : ForwardIndexType {
	public func successor() -> UnicodeScalar {
	return UnicodeScalar(value + 1)
	}
	}

	var operatorHeads: [UnicodeScalar] = Array("=-+!*%<>&\|^~?".unicodeScalars)
	operatorHeads += Array("\u{00A1}" ... "\u{00A7}")

	/*
	* This work is free. You can redistribute it and/or modify it under the
	* terms of the Do What The Fuck You Want To Public License, Version 2,
	* as published by Sam Hocevar. See the COPYING file for more details.
	*/
	/*
	* Easing Functions - inspired from http://gizma.com/easing/
	* only considering the t value for the range [0, 1] => [0, 1]
	*/
	EasingFunctions = {

	- (UIImage *)pspdf_preloadedImage {
	CGImageRef image = self.CGImage;

	// make a bitmap context of a suitable size to draw to, forcing decode
	size_t width = CGImageGetWidth(image);
	size_t height = CGImageGetHeight(image);

	CGColorSpaceRef colourSpace = CGColorSpaceCreateDeviceRGB();
	CGContextRef imageContext = CGBitmapContextCreate(NULL, width, height, 8, width*4, colourSpace,
	kCGImageAlphaPremultipliedFirst \| kCGBitmapByteOrder32Little);