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Discussion on: The Lies of "===" operator

bipinrajbhar profile image
Bipin Rajbhar

0 === -0 is true because 0 doesn't have sign

NaN === NaN is false because, according to IEEE 754 specifications any operation performed on NaN values should yield a false value or should raise an error.

val_baca profile image
Valentin Baca

-0 does in fact have a sign:

Moreover, there are two zero values, called signed zeros: the sign bit specifies whether a zero is +0 (positive zero) or −0 (negative zero).

craigmc08 profile image
Craig McIlwrath

That same Wikipedia article specifies that 0 and -0 should compare as equal.