Rename various "concrete opaque type" things to say "hidden type" #147109
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| Some changes occurred in exhaustiveness checking cc @Nadrieril |
rustbot added S-waiting-on-review 
lcnr reviewed Sep 28, 2025
lcnr reviewed Sep 28, 2025
lcnr reviewed Sep 29, 2025
BoxyUwU force-pushed the rename_concrete_opaques branch from 292a521 to 66b664c Compare 
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| do u think |
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| I think it's fine 🤷 no strong preference here @bors r+ rollup=iffy |
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bors added S-waiting-on-bors Zalathar added a commit to Zalathar/rust that referenced this pull request Sep 30, 2025
…=lcnr Rename various "concrete opaque type" things to say "hidden type" r? lcnr I've found "concrete opaque type" terminology to be somewhat confusing as in conversation and when explaining opaque type stuff to people I always just talk about things in terms of hidden types. Also the hidden types of opaques are very much not *concrete* in the same sense that a type without any generic parameters is concrete which is an unfortunate overlap in terminology. I've tried to update comments to also stop referring to things as concrete opaque types but this is mostly best effort as it difficult to find all such cases amongst the massive amounts of uses of "concrete" or "hidden" across the whole compiler.
This was referenced Sep 30, 2025
bors added a commit that referenced this pull request Sep 30, 2025
Rollup of 5 pull requests Successful merges: - #140916 (Fix unuseful span in type error in some format_args!() invocations) - #146011 (Point at fn bound that introduced lifetime obligation) - #146649 (cmse: fix 'region variables should not be hashed') - #147109 (Rename various "concrete opaque type" things to say "hidden type") - #147167 (Don't condition RUSTDOC_LIBDIR on `--no-doc`) r? `@ghost` `@rustbot` modify labels: rollup
rust-timer added a commit that referenced this pull request Sep 30, 2025
Rollup merge of #147109 - BoxyUwU:rename_concrete_opaques, r=lcnr Rename various "concrete opaque type" things to say "hidden type" r? lcnr I've found "concrete opaque type" terminology to be somewhat confusing as in conversation and when explaining opaque type stuff to people I always just talk about things in terms of hidden types. Also the hidden types of opaques are very much not *concrete* in the same sense that a type without any generic parameters is concrete which is an unfortunate overlap in terminology. I've tried to update comments to also stop referring to things as concrete opaque types but this is mostly best effort as it difficult to find all such cases amongst the massive amounts of uses of "concrete" or "hidden" across the whole compiler.
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r? lcnr
I've found "concrete opaque type" terminology to be somewhat confusing as in conversation and when explaining opaque type stuff to people I always just talk about things in terms of hidden types. Also the hidden types of opaques are very much not concrete in the same sense that a type without any generic parameters is concrete which is an unfortunate overlap in terminology.
I've tried to update comments to also stop referring to things as concrete opaque types but this is mostly best effort as it difficult to find all such cases amongst the massive amounts of uses of "concrete" or "hidden" across the whole compiler.