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JavaScript

Henrik Christensen
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.a{fill-rule:evenodd;}techdegree
Henrik Christensen
Python Web Development Techdegree Student 38,322 Points

typeof problem

Hi,

Given the function below why does validArg([3]) return true when typeof [3] == "object"?

function validArg(arg) {
    for (var i = 0; i < arg.length; i++) {
      if (typeof arg[i] != "number") {
        return false;
      }
    }

    return true;
  }

1 Answer

Steven Parker
Steven Parker
220,501 Points

This function does not test the argument directly, it loops through the argument array, testing the values that the array contains.

Since "[3]" has only one element, and that element is a number, the function returns "true".