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<!DOCTYPE html> <html> <body> <p>Setting a default value to a function parameter.</p> <p id="demo"></p> <script> function myFunction(x, y) { y = y || 0; return x * y; } document.getElementById("demo").innerHTML = myFunction(4); </script> </body> <!-- Mirrored from www.w3schools.com/js/tryit.asp?filename=tryjs_function_undefined2 by HTTrack Website Copier/3.x [XR&CO'2014], Fri, 23 Jan 2015 07:36:11 GMT --> </html>
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