My App
Phase 5 — Python-specific Features

enumerate

Loop over a list while also getting the index

enumerate() wraps an iterable so each loop turn gives you both the index and the value.

users = ["John", "David"]

for index, user in enumerate(users):
    print(index, user)
0 John
1 David

JS has a couple of ways to get the same result:

const users = ['John', 'David'];

users.forEach((user, index) => {
  console.log(index, user);
});

// or, if you need a real `for` loop:
for (const [index, user] of users.entries()) {
  console.log(index, user);
}

arr.entries() is the closest match — it also gives you [index, value] pairs, same shape as Python's enumerate().

Starting from a different number

Pass start if you don't want to begin counting at 0:

for index, user in enumerate(users, start=1):
    print(index, user)
1 John
2 David

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