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Python Python Basics (2015) Logic in Python Around and Around

Posted by Luke Bennett
Luke Bennett
10,265 Points

While loops - Around and Around Tutorial

In the around and around tutorial why does the 'while' loop stop when it reaches 1? Why does it not carry on forever? I do not see where it becomes false.

1 Answer

James J. McCombie
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James J. McCombie
Python Web Development Techdegree Graduate 21,199 Points
James J. McCombie
.a{fill-rule:evenodd;}techdegree seal-36
James J. McCombie
Python Web Development Techdegree Graduate 21,199 Points

Do you mean the:

start = 0 while start: print(start) start -= 1

loop?

if so its because of 'truthy' and 'falsey' things. whatever is to the right of the 'while' keyword is evaluated to a true or false value. zero, empty strings, and others are falsey, 1 - 10 are truthy. So the loop runs until start = 0, which means while False, and the loop breaks

Luke Bennett
Luke Bennett
10,265 Points

That's it!

Ahhh Okay, thank you, I remember the lesson now.

Thank you very much :)