سؤال 79

The function label is written as (value = "new") => value. Which pair of call results is correct?

label(undefined) gives undefined; label(null) gives new
label(undefined) gives new; label(null) gives new
label(undefined) gives new; label(null) gives nullپاسخ درست
Both calls throw because defaults require no argument syntax

توضیح

A default initializer is selected for a missing argument or one explicitly equal to undefined, so label(undefined) gives new. Passing null supplies an actual argument, so label(null) preserves null rather than treating it as absent.

توضیح

ادامهٔ این آزمون