Read again Memory Safety chapter of The Swift programming language, then chapter Deinitialization, then Strings and Characters. Some details of Multiline String Literals slippered from my mind:

// `multilineString` doesn't have line breaks
let multilineString = """
These are the same.
// Multi line literal could have \ at end of each line meaning it will be no new line there 
let softWrappedQuotation = """
The White Rabbit put on his spectacles.  "Where shall I begin, \
please your Majesty?" he asked.

"Begin at the beginning," the King said gravely, "and go on \
till you come to the end; then stop."

This shows strings are tricky collections:

// Concatenating two strings of length 1 creates a string of length 1
let combinedEAcuteS1: String = "\u{65}"         // e
print(combinedEAcuteS1, combinedEAcuteS1.count) // e 1
let combinedEAcuteS2: String = "\u{301}"        //  ́
print(combinedEAcuteS2, combinedEAcuteS1.count) //  ́ 1
let combinedEAcute2: String = combinedEAcuteS1 + combinedEAcuteS2
print(combinedEAcute2, combinedEAcute2.count)   // é 1