Add methods for cumulative folding and prefix sums #10789
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straight-shoota
approved these changes
Jun 6, 2021
ryanprior
reviewed
Jun 6, 2021
jhass
approved these changes
Jun 12, 2021
This reverts commit d9ee24c.
jhass
approved these changes
Jun 14, 2021
asterite
reviewed
Jun 18, 2021
| @@ -44,6 +44,92 @@ describe Iterator do | |||
| end | |||
| end | |||
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| describe "#accumulate" do | |||
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I think we can use the new Iterator spec helpers here
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But it can be done in a separate PR
asterite
reviewed
Jun 18, 2021
| # the collection. This initial value is always present in the returned array. | ||
| # | ||
| # ``` | ||
| # [1, 3, 5, 7].accumulate(9) { |x, y| x * y } # => [9, 9, 27, 135, 945] |
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Can we use a different value than 1 here? It might make the behavior easier to understand
asterite
approved these changes
Jun 18, 2021
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Closes #8496.
The interfaces (
Enumerable#accumulate,Iterator#accumulate,Iterable#each_accumulated) are based on #8496 (comment), i.e. block-less overloads are used for prefix sums. All overloads are O(n).