This the first post of a series I’m doing on how to optimize your app’s binaries. The post is more of a high level intro. Depending on the action (build, run, test, profile, analyze, archive) of your scheme, the process will have all or some of the following steps: Dependency analyzing What happens when you press build? So the first step is for the build system to take the build description, your Xcode project file....
Whats the Difference Between an App (bundle) and a Binary
A binary is the linked product of all your source code. It’s executable. You can run commands against it. An app, is merely a wrapper/directory, which includes that binary and other things. How do you create a binary? First it’s import to understand what a binary is. You’ve used them every day in the terminal. Examples: ls, cp, mkdir. You pass certain parameters to them. They don’t have any file extension....
The power and expressiveness of Swift ranges
Ranges in swift are super simple to create. Yet they come in various forms. let r1 = 1...3 let r2 = 1..<3 let r3 = ...3 let r4 = 3... let r5 = ..<3 Now they all have range like characteristics, but have slightly different traits. It’s because they’re actually different types. Different Range Types let r1 = 1...3 // ClosedRange<Int> let r2 = 1..<3 // Range<Int> let r3 = ....
How cp case-insensitivity can cause chaos!
Been doing Advent of Code in the last couple of days. I completed Day 6. I have been doing it from an Xcode project. However I was thinking it would be nice if I could do it from command line. So I started to do some code clean up. First I started with renaming the folder from AOC to aoc. I did: cp -r AOC aoc I saw a new aoc directory created....
How to Think Recursively - Part 2
Please read How to Think Recursively before reading this post. This post re-applies the steps mentioned in the previous post on a more challenging question. Question Return all possible ways we can generate a well-formed parenthesis? Examples: if n = 1 then we can only form () if n = 2 then we can form (()) and ()() if n = 3 then we can form ((())), (())(), ()(()), (()()), (), (), () Let’s try applying our 4 steps:...
How to Think Recursively - Part 1
These articles are about the gotchas I faced when trying to think recursively. The logic in principle should apply to most recursive problems. In this post, I will use the following question as a point of reference: ‘Count how many ways you can climb a staircase. You can jump either one step at a time or two steps at a time.’ Example if there are 3 stair cases then you can either jump:...
Why does pod lib lint suddenly fail to build?
I made some changes to the repo of our private pod. Pushed up my branch. Tests all ran. Then my colleague asked for some updates to my PR (pull request). I made changes and pushed it to GH. I wanted to merge the changes. But then CI was failing. So I ran CI again. It failed again. They say third time is the charm. So I ran it two more times....
How Understanding State Machines Helps With Building Trees and Graphs
My team was dealing with a large flow, where user can transition from multiple states or sometimes skip certain states. We didn’t have a centralized controller, every screen just had logic on where it should go next. This made it difficult for us to see all our logic at once. We asked around and was told state machines are a good fit for our situation. State machines are void of any UX....
What Resources Does Apple Provide for teaching iOS to students?
Note: This post has got a bit longer than what I originally intended. You might want to skip to the very end to see the verdict and table first and then read again. I’ve started an iOS training course in my local community. At the beginning I thought it would be easy for me to just start training people with whatever I know. Later I decided to look at some available resources....
Longest Increasing Subsequence Length
What’s a subsequence? Any selection of items from the original array. The selection must respect the order. Meaning for [1,2,3,4,5] only two of the four below are subsequences: [1,2,3,4,5] ✅ [1,4,3,2,5] ❌ order not respected [1,2,5] ✅ [5,1] ❌ order not respected What’s the difference between a subsequence and a subarray? Subarray, is just like subsequence, that is order must be respected. Additionally the sub-array has to be made of continuous elements....