Frank Schmitt frankus

For testability purposes (and to make things easier to reason about), sometimes it's nice if methods in a class are pure functions, that is, they don't contain any explicit or implicit references to self, or really anything other than the arguments that are passed in.

In the painfully contrived example below, method is a method (because it references both a property and another method using self) and isEven is a pure function (because it doesn't).

class MyClass {
  let number: Int
  
 init(number: Int) {

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I hereby claim:

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I am frankus (https://keybase.io/frankus) on keybase.
I have a public key whose fingerprint is 2A7F B0A5 A84C 5A18 8750 94B6 242B C728 204F BB64

To claim this, I am signing this object:

	struct MyStruct: Decodable {
	let data: Data

	static func decodeHexData(_ decoder: Decoder) throws -> Data {
	let container = try decoder.singleValueContainer()
	let stringValue = try container.decode(String.self)

	guard let data = Data(hexString: stringValue) else {
	throw MyStructError.invalidHexString(stringValue)
	}

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	+ (NSValueTransformer *)URLArrayTransformer {
	return [MTLValueTransformer reversibleTransformerWithForwardBlock:^NSArray (NSArray URLStrings) {
	NSMutableArray *result = [NSMutableArray arrayWithCapacity:[URLStrings count]];
	for (NSString *URLString in URLStrings) {
	[result addObject:[NSURL URLWithString:URLString]];
	}
	return result;
	} reverseBlock:^NSArray (NSArray URLs) {
	NSMutableArray *result = [NSMutableArray arrayWithCapacity:[URLs count]];
	for (NSURL *URL in URLs) {

	//
	// ExtendedCollectionView.h
	//
	// Created by Frank Schmitt on 7/11/14.
	//

	@interface ExtendedCollectionView : UICollectionView

	@property (nonatomic) UIEdgeInsets touchAreaInsets;

	/**
	Returns the index paths of the rows affected by switching between two
	sorted (but not necessarily unique) arrays.

	@param old The array to be switched from.
	@param new The array to be switched to.
	@param keyPath the key path to compare ("@self" to use raw value)

	@return An array of three arrays, the first containing index paths
	for modified rows, the second for deleted rows, and the third for

	- (BOOL)textField:(UITextField )textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString )string {
	if (textField == self.myPhoneTextField) {
	NSString *newText = [textField.text stringByReplacingCharactersInRange:range withString:string];
	BOOL deleting = [newText length] < [textField.text length];

	NSString *stripppedNumber = [newText stringByReplacingOccurrencesOfString:@"[^0-9]" withString:@"" options:NSRegularExpressionSearch range:NSMakeRange(0, [newText length])];
	NSUInteger digits = [stripppedNumber length];

	if (digits > 10)
	stripppedNumber = [stripppedNumber substringToIndex:10];