Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.python > #101336

Re: True/False value testing

Show all headers | View raw

Chris Angelico <rosuav@gmail.com>:

>> Stirring the pot:
>>
>>    >>> (2 < 3) is True
>>    True
>>
>> but is that guaranteed?
>
> Yes. When you do comparisons involving integers, the result is an
> actual boolean value - not just a truthy value, but the exact value
> True or False.

I couldn't locate that bold statement in the language spec (see <URL:
https://docs.python.org/3/library/stdtypes.html#comparisons>).

However, I *could* find this statement:

   1. [or] is a short-circuit operator, so it only evaluates the second
      argument if the first one is False.

   2. [and] is a short-circuit operator, so it only evaluates the second
      argument if the first one is True.

   <URL: https://docs.python.org/3/library/stdtypes.html#boolean-op
   erations-and-or-not>

The wording is very unfortunate (both the use of the word "is" and the
explicit references to the builtin constants False and True).


Marko

Back to comp.lang.python | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

True/False value testing "ast" <nomail@invalid.com> - 2016-01-07 11:36 +0100
  Re: True/False value testing Peter Otten <__peter__@web.de> - 2016-01-07 11:48 +0100
  Re: True/False value testing Chris Angelico <rosuav@gmail.com> - 2016-01-07 21:49 +1100
    Re: True/False value testing Marko Rauhamaa <marko@pacujo.net> - 2016-01-07 13:19 +0200
      Re: True/False value testing Chris Angelico <rosuav@gmail.com> - 2016-01-07 22:50 +1100
        Re: True/False value testing Marko Rauhamaa <marko@pacujo.net> - 2016-01-07 14:07 +0200
          Re: True/False value testing Chris Angelico <rosuav@gmail.com> - 2016-01-07 23:38 +1100
  Re: True/False value testing "ast" <nomail@invalid.com> - 2016-01-07 12:11 +0100

csiph-web