Swift for Ruby & Javascript Developers
Ruby
i = 3
@name = "John Doe"
self.cat = Cat.new(:tabby)
puts self.cat
Javascript
var i = 3; // or let this.name = "John Doe"; this.cat = new Cat('tabby'); console.log(this.cat);
Swift
let i = 3
self.name = "John Doe"
self.cat = Cat("tabby")
print(self.cat)
Ruby
a = 1 # assign an integer b = "a string" # assign a string c = [2, 4, 6, 8] # assign an array d = {abc: "some", xyz: "values"} # dictionary / hash
VARIABLES
Javascript
let a = 1;
let b = "a string";
let c = [2, 4, 6, 8];
let d = {"abc": "some", "xyz": "values"};
VARIABLES
note: let is the new, improved alternative to var in ES6, because reasons.
Swift
let a = 1 let b = "a string" let c = [2, 4, 6, 8] let d = ["abc": "some", "xyz": "values"]
VARIABLES
note: let here is NOT the same thing as let in ES6. let in Swift creates a constant, aka a "variable" that is actually immutable.
Ruby
a = 12345
b = "a string with #{a} in it"
puts b.include? "123" # true
STRING INTERPOLATION
Javascript (ES6)
let a = 12345;
let b = `a string with ${a} in it`;
console.log(b.indexOf("123") != -1); // true
console.log(b.includes("123")); // ES6: true
STRING INTERPOLATION
note: that backticks syntax looks pretty eewww, but it's definitely useful
Swift
let a = 12345 let b = "a string with \(a) in it"
print(b.contains("123")) // true
STRING INTERPOLATION
note: that backticks syntax looks pretty eewww, but it's definitely useful
Ruby
range1 = 1..5 # 1, 2, 3, 4, 5
range2 = 1...5 # 1, 2, 3, 4
RANGES
Javascript
RANGES
(just kidding, Javascript doesn't have ranges)
Swift
let range1 = 1..<5 # 1, 2, 3, 4
let range2 = 1...5 # 1, 2, 3, 4, 5
RANGES
note: OMG, ... is the opposite of Ruby!
Ruby
myArray = [1,7,8] growingArray = [] myArray.each do |i| growingArray << i + 23 if i > 2 end
ARRAYS & LOOPS
Javascript
var myArray = [1,7,8];
var growingArray = [];
myArray.forEach(function(i) {
if (i > 2) { growingArray.push(i + 23) }
});
ARRAYS & LOOPS
Swift
let myArray = [1,7,8]
var growingArray = [Int]()
myArray.forEach {(i: Int) in
if i > 2 { growingArray.append(i + 23) }
}
ARRAYS & LOOPS
Ruby
class Frog < PondAnimal def initialize super self.sound = "ribbit" end end
OOP (Object-Oriented Programming)
Javascript (ES6)
class Frog extends PondAnimal {
constructor() {
super();
this.sound = "ribbit";
}
}
OOP (Object-Oriented Programming)
note: the new OOP stuff in ES6 is really, really nice
Swift
class Frog: PondAnimal {
override init() {
super.init()
self.sound = "ribbit"
}
}
OOP (Object-Oriented Programming)
note: seeing a pattern here? Swift syntax is surprisingly easy on the eyes (most of the time)
Let's Run Some Code
code examples at
Swift Ecosystem for Servers
- Foundation Framework
https://swift.org/core-libraries/#foundation - Server APIs Project
https://swift.org/server-apis/ - IBM-Swift/Kitura: A web framework and HTTP server.
https://github.com/ibm-swift/kitura - Express: Swift Web Application Framework
http://swiftexpress.io/ - Vapor (Web Framework for Swift)
http://qutheory.io/ - Swifton (Ruby on Rails inspired)
https://github.com/necolt/Swifton - Stencil templating language (very similar to Liquid)
https://github.com/kylef/Stencil
Stencil looks like:
There are {{ articles.count }} articles.
{% for article in articles %}
- {{ article.title }} by {{ article.author }}.
{% endfor %}
note: yep, this looks just like Liquid
Q. Is Swift ready for prime time?
A. Yes.
I think Apple's really gone all out in making Swift a true cross-platform, performant, general-purpose programming language with a touch of pizazz.
Well done.