While statement

Question

is "while true" a python statement or do i have to use the word "true" ?

Answer 1

Here is the wiki

https://will.python.org/moin/WhileLoop

It clearly states true, false and none are keywords in python3 as well as not( not in the wiki)

It also gives an example on how using True as an argument can simplify your code.

Answer 2

while True means loop forever. The while statement takes an expression and executes the loop body while the expression evaluates to (boolean) "true". True always evaluates to boolean "true" and thus executes the loop body indefinitely. It's an idiom that you'll just get used to eventually! Most languages you're likely to encounter have equivalent idioms.

Note that most languages usually have some mechanism for breaking out of the loop early. for python u could use a break, or any statement that will produce the Boolean false at some point.

Answer 3

True not true

while 1==1 is okay too

Answer 4

ok great thanks.. apparently "true" has to be capitalized for it to work. maybe thats why it was not working

Answer 5

so "while true" does something specific in python or would " while crap" do the same thing ?

Answer 6

while {expression that evaluates to True or False}

that means:

while True
while 1
while 2<3
while not False

but you do not enter loop with:
while False
while 0
while 3>4

0 and 1 are special cases:
0 is a kind of False -- falsey
1 is a kind of True - truthy
there are more special cases for truthy and falsey

Answer 7

i guess im not clear... does the word "true" actually do something or is just a word to track what your doing ?

Answer 8

True is a constant in python

3+2 evaluates to 5
3<5 evaluates to True

You are right, it is a kind of magic:
Normally while expects an expression to evaluate.
for endless loops we do the work for the while loop and give directly the result.
True is the easiest expression to evaluate:
True is True

Answer 9

ok.... i guess i get it.. thanks

Answer 10

the code before can be hard, strong smelling and nasty, even wrong.
True is True.

Answer 11

It is not python-specific.
one can find while true or similiar in many nearly all languages.