# Opaque result types

**URL:** <https://forums.swift.org/t/opaque-result-types/15645>\
**Category:** Pitches\
**Created:** [August 29, 2018, 9:49pm UTC](https://forums.swift.org/t/opaque-result-types/15645 "2018-08-29T21:49:17Z")\
**Posts on this page:** 1\
**Showing post:** 349

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**Author:** ![Moximillian](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/moximillian/32/3055_2.png) [@Moximillian](https://forums.swift.org/u/Moximillian)\
**Post date:** [March 5, 2019, 7:47pm UTC](https://forums.swift.org/t/opaque-result-types/15645/349 "2019-03-05T19:47:10Z")

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> [@zwaldowski](#):
>
> Given the `Collection` confusion — that it's purportedly not a good example for how we'd want to use this first version of opaque types, and that ABI stability saddles the stdlib with its `LazyFilterFlattenCrunchyRawUnbonedCollection` types — what _is_ the intended, platonic ideal use case? There are lots of examples from forum users about how they'd _like_ to use them, which is good and valuable, but not the same.

EDIT:  
This [comment](https://forums.swift.org/t/se-0244-opaque-result-types/21252/19) from @nuclearace is enough to convince me that there is a real need for Opaque result types beyond Collection in Foundation. So it makes sense to have a [proposal](https://forums.swift.org/t/se-0244-opaque-result-types/21252) .

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