Eq and Ord instances for Prio queues #106
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* Make the `Eq` and `Ord` instances for `Prio` queues compare the queues in fully sorted form—that is, as key-value maps. This seems to be the only way to make these instances make any real kind of sense. * Document the "nondeterministic" nature of `Prio` queues.
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@konsumlamm Any comments? |
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Sorry, I don't have much time lately, I'll try to keep up with your PRs.
I'm a bit skeptical about requiring Ord a for Eq (MinPQueue k a). That would be a breaking change and many value types I can imagine don't necessarily have an Ord instance (although I can't think of many use cases for an Eq instance anyway...). I'd be fine with just documenting that the Eq instance is non-deterministic and recommending (==) `on` toAscList. However, then we also can't change the Ord instance, since they should be compatible.
Btw, please try to link related issues, like #78. Is this supposed to close #78?
| @@ -128,7 +128,7 @@ pattern Empty = Internals.Empty | |||
| infixr 5 :< | |||
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| -- | A bidirectional pattern synonym for working with the minimum view of a | |||
| -- 'MinPQueue'. Using @:<@ to construct a queue performs an insertion in | |||
| -- 'Prio.MinPQueue'. Using @:<@ to construct a queue performs an insertion in | |||
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This should have been 'MinQueue', no?
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Yes, I'll fix that.
| -- | \(O(n)\). @'mapKeysMonotonic' f q == 'Data.PQueue.Prio.Min.mapKeys' f q@, | ||
| -- but only works when @f@ is strictly monotonic. | ||
| -- /The precondition is not checked./ | ||
| -- This function has better performance than 'Data.PQueue.Prio.Min.mapKeys'. | ||
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| -- | \(O(n)\). @'mapKeysMonotonic' f q == 'Data.PQueue.Prio.Min.mapKeys' f q@, | |
| -- but only works when @f@ is strictly monotonic. | |
| -- /The precondition is not checked./ | |
| -- This function has better performance than 'Data.PQueue.Prio.Min.mapKeys'. | |
| -- | \(O(n)\). @'mapKeysMonotonic' f q == 'Data.PQueue.Prio.Min.mapKeys' f q@, | |
| -- but only works when @f@ is strictly monotonic. | |
| -- /The precondition is not checked./ | |
| -- This function has better performance than 'Data.PQueue.Prio.Min.mapKeys'. |
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What am I missing?
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The change is to remove the blank line, unfortunately the diff doesn't show this.
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I really want the |
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Yes this should close #78. |
Make the
EqandOrdinstances forPrioqueues compare the queues in fully sorted form—that is, as key-value maps. This seems to be the only way to make these instances make any real kind of sense.Document the "nondeterministic" nature of
Prioqueues.