How to navigate the return values from calls to Cocoa Foundation framework

Hello,

I made the following call to get an array of ranges of a matching regex :

	set theText to current application's class "NSString"'s stringWithString:html
	set regexPattern to "url\\([" & (ASCII character 34) & ",'](https?:\\/\\/)?([\\da-z\\.-]+)\\.([a-z\\.]{2,6})([\\/\\w\\.-]*)*\\/?"
	set urlRegex to current application's class "NSRegularExpression"'s regularExpressionWithPattern:(regexPattern) options:(0) |error|:(missing value)
	set matchRanges to (urlRegex's matchesInString:(theText) options:(0) range:({0, theText's |length|()}))'s valueForKey:("range")

I get the following result :

item 1 of (NSArray) {(NSConcreteValue) NSRange: {11780, 52}, (NSConcreteValue) NSRange: {13066, 52}, (NSConcreteValue) NSRange: {15247, 40}, (NSConcreteValue) NSRange: {16288, 39}, (NSConcreteValue) NSRange: {17788, 36}, (NSConcreteValue) NSRange: {18596, 36}, (NSConcreteValue) NSRange: {19806, 75}, (NSConcreteValue) NSRange: {20807, 49}, (NSConcreteValue) NSRange: {21287, 63}, (NSConcreteValue) NSRange: {23892, 46}, (NSConcreteValue) NSRange: {24715, 35}, (NSConcreteValue) NSRange: {25182, 63}, (NSConcreteValue) NSRange: {25667, 44}, (NSConcreteValue) NSRange: {26011, 28}, (NSConcreteValue) NSRange: {26394, 66}, (NSConcreteValue) NSRange: {26769, 72}, (NSConcreteValue) NSRange: {28682, 66}, (NSConcreteValue) NSRange: {29576, 66}, (NSConcreteValue) NSRange: {31236, 32}}

The list of items is a NSArray which means I can’t do :

	repeat with range in matchRanges
		set element to range
		set pos to item 1 of element
		set len to item 2 of element
	end repeat

How do I get the position and length attributes of each NSRange ?
I have looked for AppleScript documentation on Apple Developer but can only find documents related to the scripting bridge.
Thanks,
Regards