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JavaScript

Henrik Christensen
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Henrik Christensen
Python Web Development Techdegree Student 38,322 Points
Posted by Henrik Christensen
.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
229,732 Points
Steven Parker
Steven Parker
229,732 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".