Eval/Delete Test

by Michael Geary

HTML

<script src="https://getfirebug.com/firebug-lite.js"></script>

JavaScript

console.log( 'Normal code, a = 1' );
var a = 1;
console.log( 'a is', typeof a, a );
console.log( 'window.a is', typeof window.a, window.a );
console.log( 'delete a OK?', delete a );
console.log( 'delete window.a OK?', delete window.a );
console.log( 'a is now', typeof a, a );
console.log( 'window.a is now', typeof window.a, window.a );

console.log( ' ' );

console.log( 'Eval code, b = 1' );
eval( 'var b = 1;' );
console.log( 'delete b OK?', delete b );
console.log( 'b is now', typeof b, window.b );