After Effects expression syntax error

Surrounded by developers in this high-tech country that is Israel, I became more curious about coding language of After Effects. Trying to understand the basics of expression on After Effects today...............and I get this message "...SYNTAX ERROR..." Took a bit of fussing around to make this work. Expressions are so useful...need to get more into it and tap into another world of AE possibilities! Anyhow, I applied an expression on the scale of the shape layers which reacts to the animated background alpha information. Love how simple/quick it is to animate many shapes uniformly with two short lines of code. Happy honeycomb syntax error. Woo!


This is how the expression look like:
sourceLayer = thisComp.layer("Transition Control 2"); sampleSize = [1,1]; samplePoint = transform.position; colour= sourceLayer.sampleImage(samplePoint,sampleSize); x=colour[0]*100; [x,x]

Copy past and apply to everythang!