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Add a variant unfoldrExactN, returning the resulting generator

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#447 3 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Stale
Tech stack
haskell
Domain
data

Research direction

Start from the requested unfoldrExactN_ signature and compare it with the vector package's existing unfold APIs; the issue does not name implementation files or tests. Clarify the API and semantics for returning the final generator state, then add coverage showing that both the Vector result and resulting b are correct.

Written by the indexing model from the issue text.

Description

help-wanted

I have a job for

unfoldrExactN_ :: Int -> (b -> (a, b)) -> b -> (Vector a, b)

but it is surprisingly difficult to emulate: the best I managed to do was put b into State and use replicateM.

How do you feel about extending vector with such function?

Dominant language
Haskell
Stars
401
Forks
145
PR merge metrics
No merged PRs in 30d

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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