Add NonEmptyList#fromFoldable #1594
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| @@ -313,6 +313,9 @@ object NonEmptyList extends NonEmptyListInstances { | |||
| case h :: t => NonEmptyList(h, t) | |||
| } | |||
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| def fromFoldable[F[_], A](fa: F[A])(implicit F: Foldable[F]): Eval[Option[NonEmptyList[A]]] = | |||
| F.reduceRightToOption(fa)(x => NonEmptyList.of(x))((e,acc) => Later(e :: acc.value)) | |||
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What about NonEmptyList.fromList(F.toList(fa)) ?
The Foldable#toList implementation using a mutable.ListBuffer, which is overridden in most Foldable instances (eg List just returns the list itself, Vector calls toList, etc), should be more efficient than prepending to a NonEmptyList.
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Fine with me, I thought that going through a |
Codecov Report
@@ Coverage Diff @@
## master #1594 +/- ##
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+ Coverage 92.52% 92.52% +<.01%
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Files 249 249
Lines 3974 3975 +1
Branches 131 130 -1
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+ Hits 3677 3678 +1
Misses 297 297
Continue to review full report at Codecov.
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Sorry about that I accidentally clicked the close button. There's a small argument for adding this method to the 👍 thanks! |
Adds a new method
NonEmptyList#fromFoldable. This generalizesNonEmptyList.fromListsuch that you can also create aNonEmptyListfrom anything that has aFoldableinstance, e.g.,Vector,Set, ...