Accessing the index in 'for' loops

To access the index in a 'for' loop in Python, you can use the built-in 'enumerate' function. This function takes an iterable (such as a list or string) as an argument and returns a tuple containing the index and the value at each iteration.

Here is an example of using 'enumerate' in a 'for' loop:

Accessing the index in a for loop over an enum in Python

names = ['Alice', 'Bob', 'Charlie', 'Dave']

for i, name in enumerate(names):
  print(f'{i}: {name}')

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This will print out the following:

enumerate output

0: Alice
1: Bob
2: Charlie
3: Dave

You can also access the index directly by using the 'range' function in the 'for' loop. This will give you a sequence of numbers that you can use as the indices of the iterable.

For example:

Accessing the index in a for loop over the integer range of an array length in Python

names = ['Alice', 'Bob', 'Charlie', 'Dave']

for i in range(len(names)):
  print(f'{i}: {names[i]}')

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This will also print out the following:

for in range output

0: Alice
1: Bob
2: Charlie
3: Dave