Basic operators

Swift’s operators are mostly similar to that of common programming languages, but there were a few that stood out for me which I thought I should write about today.

Nil-Coalescing Operator

The simplicity of this operator really stood to me and it is one that I suspect I will be using a lot considering that Swift uses optionals which often require checking whether a value is a nil or not. The Nil-coalescing operator does this in a much cleaner way.

Instead of checking and assigning a default value like below

    myOptional ! = nil ? myOptional! : alternativeValue

Nil coalescing has a cleaner way which is

    myOptional ?? alternativeValue

Range Operators

Range operators are common in other languages, I’m writing about them because I tend to mix them up, but I’m certain this will improve the more I use them.

Closed Range operator

(a...b) This defines a range that runs from a to b and includes both a and b.

    for index in 1..3 {
    	print("\(index) times 10 is \(index * 10) "
    //1 times 10 is 10
    //2 times 10 is 20
    //3 times 10 is 30

Half-open range operator

(a..<b) This defines a range that starts and includes a but doesn’t include b that’s why it’s said to be half-open.

   let rugbyGroups = ["pool-a", "pool-b", "pool-c", "pool-d"]
    let count = rugbyGroups.count
    for i in 0..< count {
    	print("Pool \(i + 1) is called \(rugbyGroups[i])")
    //Pool 1 is called pool-a
    //Pool 2 is called pool-b
    //Pool 3 is called pool-c
    //Pool 4 is called pool-d

One-Sided Ranges

(a...) defines a range that starts from a and continues as far as possible and (...b) defines a range that starts as far as possible until b. This is called a one-sided range because the range has a value on one side.

    for group in rugbyGroups[2...] {

(..<b) defines a range that starts from as far as possible and ends at b but without including it. This is a half-open one-side operator.


Most of the operators in Swift work similar to how operators work in languages like Java and C#, these are a few that stood out for me when learning Basic operators in swift.

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