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javascript - chaining double equals == returns false

I have 3 textboxes that I am trying to do some validation that all 3 values match. I have a simple function:

    function DoesSubsriberSignatureMatch() {
    return tbNameOfSubscriber.GetText() == tbSubscriberSig1.GetText() == tbSubscriberReEnter.GetText();
}

I stepped through with the debugger, and it seems in Javascript in Chrome at least, "a"=="a" returns true, but "a"=="a"=="a" returns false.

Why?

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Take

"a"=="a"=="a"

and break it down. So first

"a" == "a"

equals what? true. Right. Now substitute true in for that first part

true == "a"

which of course is false


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