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Igor Kałużny4,337 Points
Or || statement
isNaN(lower || upper) vs isNaN(lower) || isNan(upper)
can I use the first one?
Christopher DeboveCourses Plus Student 18,373 Points
Its not the same =)
Here some examples:
lower = 3 upper = 4 isNaN(lower || upper) // return false isNaN(lower) || isNaN(upper) // return false lower = null upper = 4 isNaN(lower || upper) // return false because what's evaluated is : isNaN(upper) isNaN(lower) || isNaN(upper) // return true because : isNaN(lower) = true;
In the first case the value of argument you're passing to isNaN is the first non-falsy variable (falsy variable : "", 0, null, undefined)