Similar to the technique for re-annotated producers, this removal of accumulators works for only a sub-class of functions but it is decidable.
The population of these new lands were accumulators, adventurers on a rapidly expanding frontier.
This could result in either total elimination of accumulators or the replacement of one accumulator by another (hopefully cheaper one).
However, this annotation can be transferred to the accumulator (c. f. obstructing call) rather than the parameter to stop the accumulation.
The authors give some general advice on accumulators, but the idea behind accumulators is not generalised.
A good thing about the re-annotated consumer is that we can now attempt to remove the accumulator by safe fusion!
The second half of the series cover other important topics: abstracting over similar functions and data definitions, generative recursion, accumulator-style programming, and programming with mutation.
Here, a new algorithm for the accumulator updating36 is considered which is able to produce an estimate of the line probability.
