Using Properties or Variables, which is right?

Scripting Forums AppleScriptObjC and Xcode
#1

I have run into an AppleScriptObjC puzzle.

Both of the following script pieces work and appear to work identically.


global backgroundColor, gridColor, linesColor

property NSAffineTransform : class "NSAffineTransform" 
property NSBezierPath : class "NSBezierPath"
property NSColor : class "NSColor"

script BezierView
	property parent : class "NSView"
	
	on initWithFrame_(frame)
		continue initWithFrame_(frame)

		set backgroundColor to NSColor's whiteColor
		set gridColor to NSColor's blackColor
		set linesColor to NSColor's redColor

		return me
	end initWithFrame_
	...



property NSAffineTransform : class "NSAffineTransform" 
property NSBezierPath : class "NSBezierPath"
property NSColor : class "NSColor"

script BezierView
	property parent : class "NSView"

	property backgroundColor : NSColor's whiteColor
	property gridColor : NSColor's blackColor
	property linesColor : NSColor's redColor
	
	on initWithFrame_(frame)
		continue initWithFrame_(frame)
		return me
	end initWithFrame_
	...

Here is the puzzle: “Build and Run” work fine for both scripts, but for the second script, “Complile” in the Build menu generates an error: “Can’t make whiteColor of class “NSColor” into type reference.”

What is the real difference? Is the error an Xcode bug?

EricN

#2

I’m surprised the second example runs. Expressions in properties are resolved at compile time, but because your expression involves calling a Cocoa method, it can’t be resolved except at run time. I’d be leery of relying on it.