Understanding multiplication syntax with Lists

Question

I understand the below list concatenation:

r = [1, 2] + [False]
# Output: r = [1, 2, False]

However, I am not able to understand the below syntax:

r = [1, 2][False]
# Output: 1

Maybe dupe: [Accessing elements from a Python list using Boolean indexing](https://stackoverflow.com/q/49633222/674039) — wim, Sep 14 '22 at 01:27

score 3 · Accepted Answer · answered Sep 14 '22 at 01:23

You're defining an unnamed list, then indexing it with False. Because False has a numeric value of zero (bool is actually a subclass of int, where False has a value 0, and True has a value 1), that's equivalent to indexing it as index 0, so it's like you wrote:

__unnamed = [1, 2]
r = __unnamed[0]

Understanding multiplication syntax with Lists

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