FAQ 4.39 What is the difference between a list and an array?

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4.39: What is the difference between a list and an array?

    An array has a changeable length. A list does not. An array is something
    you can push or pop, while a list is a set of values. Some people make
    the distinction that a list is a value while an array is a variable.
    Subroutines are passed and return lists, you put things into list
    context, you initialize arrays with lists, and you foreach() across a
    list. "@" variables are arrays, anonymous arrays are arrays, arrays in
    scalar context behave like the number of elements in them, subroutines
    access their arguments through the array @_, and push/pop/shift only
    work on arrays.

    As a side note, there's no such thing as a list in scalar context. When
    you say

        $scalar = (2, 5, 7, 9);

    you're using the comma operator in scalar context, so it uses the scalar
    comma operator. There never was a list there at all! This causes the
    last value to be returned: 9.


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