On 25/07/2013, at 7:09 PM,
Here is a snippet from a real code that could benefit from non-recursive let.
[[A big blob of extremely dense code.]] _Nothing_ is going to make that easy to read. And I say that as someone who loves Haskell and is in *awe* of Oleg. I mean, if the functional rain is pouring down and Oleg says "Hey, sunny!", I normally furl my umbrella... One of the things that I find makes it hard for _me_ to read is the coding style where "do" is sneaked away out of sight. Am I alone in wanting "do" at the _beginning_ of a line so that it stands out? Do real Haskell experts just get used to using "do" so much that they don't feel it's _worth_ making visible? It's a queer thing, I always feel that the advice about keeping function bodies small is patronising nonsense for beginners and that *my* code is perfectly readable no matter how big it is, but end up wishing that *other* people kept *their* functions small. It's not as if my code were bug-free... Must be something in the water. That's relevant though. If your functions are small, you don't get enough "versions" of a variable for non-recursive let to pay off. In this specific example, as a _reader_, a much less competent reader than Oleg, the only problem I can see with using "ast1" and "header1" is that th names are not different *ENOUGH* from "ast1" and "header". I'd like names that go some towards explaining *why* 'ast1' has "_token" and "_period_values" slots that 'ast' doesn't (and for that matter, something a bit longer than 'ast', which doesn't seem to stand for Abstract Syntax Tree here), and *why* 'headers1' shouldn't include "_limit_to" and "_limit_rcvd" slots unless there is a title. All in all, a good example of code where using non-recursive let would have DECREASED readability by one person strange to the code.