Are those checks actually needed? "2.2 % 2 === 1" works just as well, so why is the isInteger check needed? Why is the isSafeInteger check needed? And "a % 2"

Are those checks actually needed? "2.2 % 2 === 1" works just as well, so why is the isInteger check needed? Why is the isSafeInteger check needed? And "a % 2" is already NaN (and thus false), although an explicit error is arguably better than silently eating it.