Though currently I am prefer to use CofferScript than Swift, I have thought that the defer of Swift2 is pretty cool. So I wrote a snippet that accomplishes the feature by using yield as like the manner of co is doing.

ruby>>
defer = (g) ->
deferred = []
go = (i) ->
{value,done} = do i.next
unless done
deferred.push value
go i
exit = ->
do f for f in deferred
process.removeListener 'exit', exit
process.on 'exit', exit
try go do g
catch then do exit

foo = (type) -> defer ->
console.log "#{type} 1"
yield -> console.log "#{type} deferred 1!"
yield -> console.log "#{type} deferred 2!"
console.log "#{type} 2"
if type == "exit" then do process.exit
else throw "throw"
console.log "3"

foo "throw"
foo "exit"

RESULTS

throw 1

throw 2

throw deferred 1!

throw deferred 2!

exit 1

exit 2

exit deferred 1!

exit deferred 2!

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