Iterating Lists

List<String> customerNames = new List<String>{'Amara', 'Ben', 'Carla'};

for (String name : customerNames) {
    System.debug('Processing: ' + name);
}

1. List<String> customerNames = new List<String>{'Amara', 'Ben', 'Carla'}; — the list to loop over.
2. (blank line)
3. for (String name : customerNames) { — this is exactly Module 7's enhanced for loop, now applied to a List directly — no index management needed.
4. System.debug('Processing: ' + name); — runs once per item.
5. } — closes the loop.

List<String> rankings = new List<String>{'Gold', 'Silver', 'Bronze'};

for (Integer i = 0; i < rankings.size(); i++) {
    System.debug('Position ' + (i + 1) + ': ' + rankings[i]);
}

1. List<String> rankings = new List<String>{'Gold', 'Silver', 'Bronze'}; — the list.
2. (blank line)
3. for (Integer i = 0; i < rankings.size(); i++) { — a classic for loop, needed because the position itself matters here.
4. System.debug('Position ' + (i + 1) + ': ' + rankings[i]); — i + 1 (since ranks start at 1, not 0) is part of the output — this is exactly the case from Module 7's "Enhanced For Loops" lesson where a classic loop is the better fit, because an enhanced for loop never exposes the current index.
5. } — closes the loop.

List<String> customerNames = new List<String>{'amara', 'ben', 'carla'};
List<String> capitalized = new List<String>();

for (String name : customerNames) {
    capitalized.add(name.capitalize());
}

System.debug(capitalized); // ['Amara', 'Ben', 'Carla']

1. List<String> customerNames = new List<String>{'amara', 'ben', 'carla'}; — the original list, all lowercase.
2. List<String> capitalized = new List<String>(); — a brand-new, empty list to collect results into.
3. (blank line)
4. for (String name : customerNames) { — loops over the original.
5. capitalized.add(name.capitalize()); — transforms each item and adds it to the new list — the original customerNames is never modified.
6. } — closes the loop.
7. (blank line)
8. System.debug(capitalized); — logs ['Amara', 'Ben', 'Carla'].

A very common pattern: loop over one List, transforming or filtering each item, and collect the results into a brand-new List.