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1 point by raymyers 5867 days ago | link | parent

True, filt doesn't touch the actions field, while sem does. However, I am usually able to replace the use of actions with filters that operate on the parsed field. I prefer this, because the filter style is a more clean and functional style -- rather than relying on side-effects. Hopefully that made sense.

I don't yet know for certain whether filters could or should be used in this particular case. enclose-sem might be the right way to go after all.

1 point by almkglor 5867 days ago | link

I'll have to defer to you on this one - I've only written a parser combinator type parser once before, and that was before I learned what it was. I did end up using something nearer to filters (i.e. acts on the returned value instead of having a separate 'actions field).

Edit: Perhaps part of the optimization of treeparse could be to eliminate the 'actions field. None of your samples used 'sem, and I might prefer 'filt for such enclosing stuff as ''bold'' and '''italics'''. The [[link]]s might be more difficult (because of the necessity of adding alphadigs after the closing bracket in [[link]]s to the actual link text but not the link target), but I think it's doable.


2 points by raymyers 5866 days ago | link

I've thought several times of removing sem in favor of filt. As features, they are very similar but filt is usually cleaner. If I don't see a compelling use case for actions soon I may indeed remove them. This would simplify the interface considerably.

Just between us, filt is actually an analogue to Haskell's monadic lift operator. They're even anagrams! (this happened by accident.)


1 point by almkglor 5866 days ago | link

Okay, I've since ported the Arki wikiformat parser to use filt instead of sem. Removing 'actions would reduce slightly the memory consumption of treeparse.