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<title>JavaScript nested function</title>
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<pre> <!-- Use pre element for work document.writeln() method -->
<script type="text/javascript">
function cal(){
var PI = 3.14;
function area(radius){
var area = PI * radius * radius;
document.writeln("Area of Circle: " + area);
}
cal.area = area;
}
var radius = 2.0;
cal();
cal.area(radius);
</script>
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