Change default insertBy implementation to work better with dlists. #18
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Instead of repeatedly computing head share the `head` computation. I've also replaced `head` and `tail` by a single call to uncons for similar reasons. In the de
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While looking into https://gitlab.haskell.org/ghc/ghc/-/issues/22425 I noticed this. This helps to pull performance for sort on dlists back to 9.4.2 levels on ghc-9.4.3 and just generally seems better to me independent of the ghc bug. |
| insertBy cmp x ys = | ||
| case uncons ys of | ||
| Nothing -> singleton x | ||
| Just (ys_head,ys_tail) -> case cmp x ys_head of |
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Style: no snake-case please. (So far, this code base has a single snake-case id only (elem_by) which sneaked in...)
Please us CamlCase or simple identifiers.
| @@ -56,6 +59,11 @@ instance ListLike (DList a) a where | |||
| --toList = D.toList | |||
| --fromList = D.fromList | |||
| replicate = D.replicate | |||
| uncons xs = case xs of | |||
| D.Nil -> Prelude.Nothing | |||
| D.Cons d_head l_tail -> Prelude.Just (d_head,fromList l_tail) | |||
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Please no snake_case.
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I hope I didn't merge this prematurely. Should I leave this repo to you Andreas? |
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I don't mind co-maintainership, I think it helps keeping repos alive. A "changes requested" should maybe not be ignored, though. There is branch protection rules that would enforce this, but I am not the repo admin here, I cannot change the settings. |
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Ok I will be more careful. I did that very early in the morning. |
Instead of repeatedly computing head share the
headcomputation.I've also replaced
headandtailby a single call to uncons for similar reasons andreplaced the default uncons implementation for DList by one based on it's pattern synonym.