IsNull() vs. IsDefined() For ColdFusion 9 Scope Detection

code-1.cfm

<!---
	Check to see if the URL and FORM scopes exist using
	both the new isNull() and the old isDefined() methods.
--->
<cfset check = {} />

<!--- Check for URL scope. --->
<cfset check.isUrlNull = isNull( url ) />
<cfset check.isUrlDefined = isDefined( "url" ) />

<!--- Check for FORM scope. --->
<cfset check.isFormNull = isNull( form ) />
<cfset check.isFormDefined = isDefined( "form" ) />


<!--- Check for scope existence. --->
<cfdump
	var="#check#"
	label="In-Page Check"
	/>