livescript - How to ignore return result -

for example

child.stdout.on \data (buffer) ->     result.stdout += buffer

-->

child.stdout.on('data', function(buffer){   return result.stdout += buffer; });

and need without return. in f# can add |> ignore how can handle in livescript?

you can prepend ! definition of function:

!(buffer) -> result.stdout += buffer

alternatively, return void

child.stdout.on \data (buffer) ->     result.stdout += buffer    void

in javascript, when return undefined (void), same not returning anything.

DIs