Add Iterator::try_collect() #308
Merged
Conversation
This file contains hidden or 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
danakj
force-pushed
the
trycollect
branch
8 times, most recently
from
884308e to
5c2befc
Compare
Closes chromium#295 try_collect can collect from an iterator of `T: Try` into a container C that supports FromIterator<T: Try> to create C<U>. The actual Try types do not need to support FromIterator then, and this replaces the need for Option or Result to implement FromIterator. We needed to add another operation on Try types for this, which is to convert from T: Try in an error state to U: Try in an error state, where they have the same (or a convertible) error type. This new concept is sus::ops::TryErrorConvertibleTo and it's accessed through sus::ops::try_preserve_error(). The TryErrorConvertibleTo concept is implemented for Option, Result and std::optional.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
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Outdated suggestions cannot be applied.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.
Closes #295
try_collectcan collect from an iterator ofT: Tryinto a containerC<U>that supportsFromIterator<T: Try>to create theC<U>.The actual
Trytypes do not need to supportFromIteratorthen, and this replaces the need forOptionorResultto implementFromIterator, if the user calls.try_collect()instead of.collect().We needed to add another operation on
Trytypes for this, which is to convert fromT: Tryin an error state toU: Tryin an error state, where they have the same (or a convertible) error type. This new concept issus::ops::TryErrorConvertibleToand it's accessed throughsus::ops::try_preserve_error().The
TryErrorConvertibleToconcept is implemented forOption,Resultandstd::optional.Then we also needed a way to take a TryType and a type Bar and produce the type TryType so that we can say try_collect<Vec> on an iterator of Option and get back Option<Vec>. This is done through
sus::ops::TryRemapOutputType<TryType, NewOutputType>.