0x00 Lesson
Swift has a few ways of writing loops
, but their underlying mechanism is the same: run some code repeatedly until a condition evaluates as false.
The most common loop in Swift is a for
loop: it will loop over arrays and ranges, and each time the loop goes around it will pull out one item and assign to a constant.
For example, here’s a range of numbers:
let count = 1...10
We can use a for loop to print each item like this:
for number in count {
print ("Number is \ (number)")
}
We can do the same with arrays:
let albums = ["Red", "1989", "Reputation"]
for album in albums {
print("\(album) is on AppleMusic")
}
If you don’t use the constant that for
loops give you, you should use an underscore instead so that Swift doesn’t create needless values:
print("Players gonna ")
for _ in 1...5 {
print ("play")
}
0x01 我的小作品
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