with-globals.coffee

@withGlobals = (prop, fn) =>
	swap = => [@[k], prop[k]] = [prop[k], @[k]] for k of prop
	try
		do swap
		do fn
	finally
		do swap

@withGlobals {alert : (v) -> console.log(v) }, =>
	@alert('funge')

try
	@alert('honge') # may cause an error
catch e
	console.log 'error'