How Do I Get a List from Python 3's `map()` Iterator?

Retrieving Mapped Lists in Python 3.x: map() as an Iterator

In Python 3.x, the map() function returns an iterator instead of a list. This change was implemented to improve memory efficiency and optimize performance. However, it poses a challenge if you need to retrieve the mapped values as a list for further processing.

Solution: Converting the Iterator to a List

To retrieve the mapped values as a list, use the list() function to convert the iterator returned by map():

mapped_list = list(map(chr, [66, 53, 0, 94]))

This code will return a list containing the mapped characters: ['B', '5', 'x00', '^'].

Alternative: Using a List Comprehension

A more concise way to convert a list into a list of mapped values is to use a list comprehension:

mapped_list = [chr(c) for c in [66, 53, 0, 94]]

This expression produces the same result as the map() example above.

Iterating Over the Map Object Directly

In certain scenarios, you may not need to convert the map object to a list. You can iterate over the map object directly using a for loop:

for c in map(chr, [65, 66, 67, 68]):
    print(c)

This code will print the characters "ABCD" without creating an unnecessary list.

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