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function write( message ) {
	document.write( "<li>" + message + ", " + ( typeof message ) + "</li>")
}

function convertBoolean( str ) {
	return str.toLowerCase() === "true";
}

var trueStr = "true";
var falseStr = "false";
var trueUppercaseStr = "TRUE";
var falseUppercaseStr = "FALSE";

write( trueStr );
write( falseStr );
write( trueUppercaseStr );
write( falseUppercaseStr );

document.write( "<br/>" )

write( convertBoolean( trueStr ) );
write( convertBoolean( falseStr ) );
write( convertBoolean( trueUppercaseStr ) );
write( convertBoolean( falseUppercaseStr ) );