why the generator expression after IF always returns True

[HenryJ]

Hi,

Why is the generator expression after IF statement always return True? Is it because the if statement only checks whether there is a new value "generated" by the expression, if so, then it will return True? But the below expression (a>100 for in x) will not generate a new value, will it?

For example:

x=[1,2,3,4,5]
y=[a**2 for a in x if (a>100 for a in x)]
print(y)

The result is

[1, 4, 9, 16, 25]

Thanks in advance!

[buran]

from the docs

In the context of Boolean operations, and also when expressions are used by control flow statements, the following values are interpreted as false: False, None, numeric zero of all types, and empty strings and containers (including strings, tuples, lists, dictionaries, sets and frozensets). All other values are interpreted as true.

https://docs.python.org/3/reference/expressions.html
generator is an object, not empty container.
also question on SO
https://stackoverflow.com/questions/7976...-exhausted

all that said, your code does not make lot of sense. what do you want to achieve?