Iterating Over Strings P1

Just like arrays, strings in Swift are sequences of characters that you can iterate over. This makes it easy to process text one character at a time using the familiar for-in loop.

When you loop through a string, Swift gives you each character in order:

let word = "Hello"

for char in word {
    print(char)
}
// H
// e
// l
// l
// o

Each char in the loop is of type Character, not String. This distinction matters when you need to compare or manipulate individual characters.

You can use this technique to analyze text, such as counting specific characters:

let message = "banana"
var countA = 0

for char in message {
    if char == "a" {
        countA += 1
    }
}

print(countA)  // 3

Notice that when comparing a character, we use a single character in quotes like "a". Swift automatically treats this as a Character when comparing with another character.