[Tutor] any(x)

[Cameron Simpson]

On 07Feb2022 22:05, Oliver Haken <Ollie.ha at outlook.com> wrote:
>I have a generator to make an infinite list of numbers

Hmm. Your computer must be _way_ faster than mine :-) Might be better to 
call it an unbounded sequence of numbers.

>Code: Select all<https://forums.sourcepython.com/viewtopic.php?t=2663#>
>
> t = 0
>u = []
>def h ():
> while True:
>  t = t + 1
>  u.append(t)
>  yield u
>h ()

As Alan remarked, you would not normally yield "u" (the list), you would 
yield each value of "t". The caling code might assemble those into a 
list, or otherwise process them.

So:

    def h(t=0):
      while True:
        yield t
        t += 1

which would yield numbers starting at 0 (by default) indefinitely.

Your expression "h()" does _not_ run the function. It prepares a 
generator to run the function and returns the generator. A generator is 
iterable, so you can iterate over the values it yields. For example in a 
for-loop. To make it clear:

    g = h()
    for i in g:
        print(i)

prints 0, then 1, etc. Usually you'd do that directly of course:

    for i in h():

>But how do I use it?

So here:

Your code:
> z = any(u)

you want:

    z = any(h())

since any() can use any iterable, and a generator is an iterable.

Cheers,
Cameron Simpson <cs at cskk.id.au>