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Comment by 1024core | Hacker News Reader

As a former Perl programmer, dabbling in Python, I keep getting reminded how awesome Perl is.

For example: I'm collecting some stats indexed by (small) ints. In Perl, I'd just say

    $collection[$index] = $stat;

Try that in Python when $index is not received in order.

Edit: Fixed typo; meant "$stat" and not "%stat"

In Python:

    dict[index] = stat

...works much the same.

The Python version blows up if the slot isn't already populated. The Perl version works in either case (there is a typo in the Perl code though).

Only if you're using a list, not a dict. I just tried it in the REPL:

    >>> foo = {}
    >>> foo[3] = 72
    >>> foo[64] = 80
    >>> foo
    {3: 72, 64: 80}

The difference is more dramatic once you have two or more dimensions:

    >>> foo = {}
    >>> foo[3][4] = 42
    Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
    KeyError: 3

Compared to:

      DB<1> $foo{3}{4} = 42

      DB<2> x \%foo
    0  HASH(0x7f9f4315c940)
       3 => HASH(0x7f9f432bb148)
          4 => 42

    tree = lambda: collections.defaultdict(tree)
    foo = tree()
    foo[3][4] = 42

I don't think I'd want or need to try that...

     \%stat;