python - While statement without expression

Question

Here is a part of a code in Python I try to figure out what it is doing:

while index < len(list) and list[index]: index += 1

I wonder what the part after the "and" (and list[index]) does exactly? I tried to add "is True" or "is False" but both did not yield the same result, so it does not check for True or False I guess. Thanks for any help!

question from:https://stackoverflow.com/questions/65936318/while-statement-without-expression

Answer 1

It checks for a Truthy value, i.e., a value that does not evaluate to False. Falsy values might include, for example, None, 0, False etc. In a nutshell, the while loop stops at the first Falsy value. For a list of Falsy values, check this answer.