Simple question on boolean function return value

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From	Janis Papanagnou <janis_papanagnou@hotmail.com>
Newsgroups	comp.lang.javascript
Subject	Simple question on boolean function return value
Date	Fri, 13 Jan 2023 15:56:49 +0100
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Today I was surprised that some old code did not work as I'd have
expected:

function friday_13th (now)
{
  return  now.getDay()==5 && now.getDate==13;
}

That function returned 'false' and also putting parenthesis around
the (sub-) expressions did not help. I had to use a local variable
to make that work:

function friday_13th (now)
{
    var f13 = now.getDay()==5 && now.getDate()==13;
    return  f13;
}

Can anyone explain that please?

Janis

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Simple question on boolean function return value Janis Papanagnou <janis_papanagnou@hotmail.com> - 2023-01-13 15:56 +0100
  Re: Simple question on boolean function return value Janis Papanagnou <janis_papanagnou@hotmail.com> - 2023-01-13 16:23 +0100
  Re: Simple question on boolean function return value V V V V V V V V V V V V V V V V V V <vvvvvvvvaaaaaaaaaaaaaaa@mail.ee> - 2023-01-28 09:05 -0800

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