Functions are objects in JavaScript, as we should know well by now, and as objects, functions have methods, including the powerful Apply, Call, and Bind methods.

// Define the original function.

var checkNumericRange = function (value) {

if (typeof value !== 'number')

return false;

else

return value >= this.minimum && value <= this.maximum;

}

// The range object will become the this value in the callback function.

var range = { minimum: 10, maximum: 20 };

// Bind the checkNumericRange function.

var boundCheckNumericRange = checkNumericRange.bind(range);

// Use the new function to check whether 12 is in the numeric range.

var result = boundCheckNumericRange (12);

document.write(result);

// Output: true