mobile - Corona: Error on removing event listeners from runtime during destroy -

i cleaning scene in corona , attempting remove event listeners in destroy event scene. i've added events in show event scene, follows:

function scene:show(event)     runtime:addeventlistener("enterframe", onframe)     runtime:addeventlistener("touch", ontap)     runtime:addeventlistener("collision", oncollision) end  function scene:destroy(event)     runtime.removeeventlistener("enterframe", onframe)     runtime.removeeventlistener("touch", ontap)     runtime:removeeventlistener("collision", oncollision) end 

i'm getting null pointer in destroy event:

?:0: attempt index field '_super' (a nil value) stack traceback:     ?: in function 'removeeventlistener' 

what "_super" trying access, , why nil? i've checked , of functions listed above (onframe, ontap, , oncollision) not nil. if has idea what's going on here, please let me know!

seems you've mistyped when calling removeeventlistener.

see:
runtime . removeeventlistener() vs
runtime : removeeventlistener()

when call removeeventlistener '.' (dot), runtime reference isn't passed implicitly first argument removeeventlistener().