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Comment by kdmccormick | Hacker News Reader

Sure, I'll try. Imagine we had two functions already defined:

  get_current_username: Returns a nonempty string iff user is logged in.

  get_balance: Returns a user's "balance" of some sort of credit or currency. Negative balances are possible.

In Python, where "falsiness" is very clearly defined by the language spec, it would be idomatic to write:

  should_render_balance = bool(get_current_username() and get_balance())

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so you get the exact same answer?

in js, Boolean('' && 0) will give you the same answer as bool('' and 0) in python.

if i code golf in python (like the article does in js), i'll also get weird-looking code and "unexpected" outputs.

valid python: 0*"string"or"other_string"

Sure, I was just responding to the question:

> Like, can you tell me a language where it does make sense to "apply AND to an empty string and a (negative?) zero"?

People do stuff like that in Python all the time. Personally, I don't do it in JS, though, because I find the conversion-to-bool rules much less predictable. In this case, though, I guess JS would behave the same.

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