borisyankov/DefinitelyTyped — pull request #3357 by Nemo157 (2014-12-23 03:04:32+00:00)
Title: Generate up to 5 argument versions of when.lift, when.attempt, when.node.lift and when.node.call

Not sure if there's any existing policy on generating the definition files, but this is the only way I could see to actually define anything over 3 argument variants without a massive hassle changing them. Even 3 arguments was getting a bit much to hand type.