Comment by cjp | Hacker News Reader

Comment by cjp | Hacker News Reader

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SPOILERS

I created a successful bothC function that looks more like the simplified version of seqC, calling fC first. But when I switch to calling gC first, I get the following failures. Am I missing something, or is this a bug in the unit test?

  PASSED No JSLint errors
  PASSED bothC(S, S, A, B) === undefined
  PASSED output === "SSA"
  PASSED bothC(S, F, A, B) === undefined
  FAILED output === "SSASFB"
  PASSED bothC(F, S, A, B) === undefined
  FAILED output === "SSASFBFSB"
  PASSED bothC(F, F, A, B) === undefined
  FAILED output === "SSASFBFSBFFB"

I'm not sure that we used the same method to get to this part, but I too ran into this output.

Interested in seeing how my solution was off, and if I was thinking about it the wrong way. Any luck?

Continuation Passing SPOILERS:

f_success = function() { gC(success, failure); }; f_failure = function() { gC(failure, failure); }; fC(f_success, f_failure);

For me, the trick here was to forget about the words "success" and "failure" because they have too much semantics embedded. I had to re-word the problem like this: call f3, if first argument of f1 and f2 are called. All other roads lead to f4. Both f1 and f2 has to be called in the chain no matter what.

Also, this is the first time I've seen such a pattern. Is there a practical application of such pattern? I think it's ok to have a single level of closure to continue execution, but if it goes to that many levels like the sample problem, it'll be a nightmare to maintain for people who have not seen your code yet.

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