String Strip / Trim in Swift

In Swift, you can remove leading and trailing whitespace from a string using trimmingCharacters(in:), which comes from Foundation, so a standalone file needs import Foundation at the top:

s.trimmingCharacters(in: .whitespaces)              // removes leading and trailing whitespace
s.trimmingCharacters(in: .whitespacesAndNewlines)   // removes whitespace and newlines from both ends

Here are some examples:

import Foundation

let s = "  hello  "
print(s.trimmingCharacters(in: .whitespaces))              // "hello"
print(s.trimmingCharacters(in: .whitespacesAndNewlines))   // "hello"

These methods return a new String — the original is not modified.