OliverLetterer

# Install libxml2 using Homebrew
# If you don't have Homebrew, follow the instructions at:
# https://github.com/mxcl/homebrew/wiki/Installation
# -------------------------------------------------------
brew install libxml2

# Install libxslt from source code
# If you don't have wget, follow the instructions at:
# http://www.mactricksandtips.com/2008/07/installing-wget-on-your-mac-for-terminal.html
# Or use Homebrew:

OliverLetterer

// Taken from http://PSPDFKit.com. This snippet is under public domain.
#define UIKitVersionNumber_iOS_7_0 0xB57
BOOL PSPDFIsUIKitFlatMode(void) {
    static BOOL isUIKitFlatMode = NO;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        // We get the modern UIKit if system is running >= iOS 7 and we were linked with >= SDK 7.
        if (kCFCoreFoundationVersionNumber >= kCFCoreFoundationVersionNumber_iOS_7_0) {
            isUIKitFlatMode = (NSVersionOfLinkTimeLibrary("UIKit") >> 16) >= UIKitVersionNumber_iOS_7_0;
        }

OliverLetterer

When dismissing a view controller on top of a view controller with UIModalPresentationPageSheet or UIModalPresentationFormSheet, the presenting view controllers frame and transform can get miscomputed on iOS 7. Here is a fix I used in SPLSpeechBubblePopoverController:

@implementation UIViewController (SPLSpeechBubblePopoverControllerHack)

+ (void)load
{
    class_swizzleSelector(self, @selector(dismissViewControllerAnimated:completion:), @selector(__SPLSpeechBubblePopoverControllerDismissViewControllerAnimated:completion:));
}

OliverLetterer

Keybase proof

I hereby claim:

• I am OliverLetterer on github.
• I am oletterer (https://keybase.io/oletterer) on keybase.
• I have a public key whose fingerprint is 9910 2A1F 6875 18FD DD01 24B0 A3CC E071 1958 9637

To claim this, I am signing this object:

OliverLetterer

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

So you're curious in learning this new thing called (Functional) Reactive Programming (FRP).

Learning it is hard, even harder by the lack of good material. When I started, I tried looking for tutorials. I found only a handful of practical guides, but they just scratched the surface and never tackled the challenge of building the whole architecture around it. Library documentations often don't help when you're trying to understand some function. I mean, honestly, look at this:

Rx.Observable.prototype.flatMapLatest(selector, [thisArg])

Projects each element of an observable sequence into a new sequence of observable sequences by incorporating the element's index and then transforms an observable sequence of observable sequences into an observable sequence producing values only from the most recent observable sequence.

OliverLetterer

@implementation NSArray (BadThirdPartyImplementation)

- (id)firstObject
{
    return self[0];
}

@end

OliverLetterer

Record a screencast with QuickTime Player

1. Connect an iOS defice with a cable
2. In QuickTime Player: Option-Cmd-N (New Movie Recording) -> Select your device from the recording menu:

Install gifify

OliverLetterer

git log HEAD...3649b6a056d72524205b57791e7c78f3ac209f7e --numstat | grep ViewController.m | awk '{ INS += $1; DEL += $2 } END { print "+" INS " -" DEL }'

OliverLetterer

#!/usr/bin/python
# Invoke this script with a Swift file containing an XCTestCase and it will
# generate an implementation for the `allTests` variable required for
# XCTestCaseProvider conformance on Linux

import sys
import re

inFile = open(sys.argv[1]) if len(sys.argv) > 1 else sys.stdin

OliverLetterer

//Given this:
NSArray *objects = @[@1, @2, @3]

//These are equivalent in behavior
NSNumber *first = [objects objectAtIndex:0]
NSNumber *second = (NSNumber *)CFArrayGetValueAtIndex(0)

//But is the code that runs the same? Not so much… in the first one we do…
objc_msgSend(objects, <selector reference>, 0)
-> http://sealiesoftware.com/msg/x86-mavericks.html