Regex instance sanity check
JavaScript
function make_a_matcher( ) {
return /a/gi;
}
var x = make_a_matcher( );
var y = make_a_matcher( );
// Beware: x and y are the same object!
x.lastIndex = 10;
alert('Does my browser have a brain?\n' + (y.lastIndex === 0) + '\n' + y.lastIndex);