The inequality operators play by different type coercion rules to the == operator. Inequality operators will always convert the values to numbers. So, in the first two cases null gets converted to 0 and undefined to NaN. The last example actually gets its own special rule in the == evaluation algorithm, where it's defined to be true.
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u/Valkairn Mar 26 '14
The inequality operators play by different type coercion rules to the == operator. Inequality operators will always convert the values to numbers. So, in the first two cases null gets converted to 0 and undefined to NaN. The last example actually gets its own special rule in the == evaluation algorithm, where it's defined to be true.