Then-make it, no promises please

The problem of callback hell is commonplace in node.js programs. If your storage is async and your logics is complex, then you hit the worst spot. Two popular solutions are promises and async.js. Unfortunately, your logics has complex branching patterns and neither solution fits well. It is not a waterfall, unfortunately. At some point, you understand that good old flowcharts and make files express your logics much much better than either callbacks or promises. OK, it is the case for then-make.

Then-make works in terms of rules and targets. You define rule functions that produce target objectss. Rules are reentrant functions that return their result either by return result or by a callback(err,result). A rule may decide that it lacks a prerequisite target, then it yields: this.yield(target); return; (TODO generators). Once the prerequisite is produced, then-make will invoke your rule once again.

Differently from classic makefiles, then-make rules decide on their prereqisites at run time. So, you rule tells the system which other prerequsites it needs this time.

For an example, see test.js.