Make CoalesceBy lazy
#801
Merged
Make CoalesceBy lazy
#801
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
In order to make `DedupByWithCount` lazy soon, I first need to be able to make `|v| (1, v)` more generic.
Similar to what is done by `core::iter::Peekable`, a nested option is now used.
This behavior is not obvious at first glance of `Iterator::next`. In it, after `let init =`, `last` is `Some(None)` in both cases. With `try_fold`, if `iter` is not exhausted then we have `*last = Some(Some(..))` (otherwise it remains `Some(None)`).
11 tasks
jswrenn
approved these changes
Nov 25, 2023
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Related to #792
To make the
CoalesceByadaptor lazy, I use a nested option again.This would make methods
coalesceanddedup[_by][_with_count]all lazy.But it required some preliminary adaptation because of
last: iter.next().map(|v| (1, v)),indedup_by_with_countfunction. Make this lazy required to delay|v| (1, v). And I therefore created structsNoCountandWithCountsharing a same behavior with the newCountItemtrait.Let me know what you think about it.