more strongly dissuade use of skip_binder
#144775
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| /// Please read <https://rustc-dev-guide.rust-lang.org/ty_module/instantiating_binders.html> | ||
| /// before using this function. It is usually better to discharge the binder using | ||
| /// `no_bound_vars` or `instantiate_bound_regions` or something like that. |
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Consider wrapping this and maybe its following paragraphs in a big warning block by surrounding it with <div class="warning"> </div> (note: there needs to be a blank line between the HTML tags and the Markdown content or else the latter would be interpreted as HTML), similarly for the EarlyBinder case.
These get rendered like so: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/struct.TyCtxt.html#method.expand_free_alias_tys
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Hm, I feel I'd need to already mark the "Accessing generic args in the returned value is generally incorrect." as a warning, but that's part of the first line.
I personally don't know how I'd restructure this to add a warning block and would merge this as is
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@bors r+ rollup I agree it'd be nice to have an actual warning here 🤔 but not sure how to structure this to do that nicely. can always do that in a follow up PR |
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Rollup of 8 pull requests Successful merges: - #139451 (Add `target_env = "macabi"` and `target_env = "sim"`) - #144039 (Use `tcx.short_string()` in more diagnostics) - #144192 (atomicrmw on pointers: move integer-pointer cast hacks into backend) - #144545 (In rustc_pattern_analysis, put `true` witnesses before `false` witnesses) - #144579 (Implement declarative (`macro_rules!`) attribute macros (RFC 3697)) - #144649 (Account for bare tuples and `Pin` methods in field searching logic) - #144775 (more strongly dissuade use of `skip_binder`) - #144987 (Enable f16 and f128 on targets that were fixed in LLVM21) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of #144775 - lcnr:skip_binder-comment, r=BoxyUwU more strongly dissuade use of `skip_binder` People unfortunately encounter `Binder` and `EarlyBinder` very early on when starting out. In these cases its often very easy to use `skip_binder` incorrectly. This makes it more explicit that it should generally not be used and points to the relevant `rustc-dev-guide` chapters. r? `@BoxyUwU`
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Rollup of 8 pull requests Successful merges: - rust-lang/rust#139451 (Add `target_env = "macabi"` and `target_env = "sim"`) - rust-lang/rust#144039 (Use `tcx.short_string()` in more diagnostics) - rust-lang/rust#144192 (atomicrmw on pointers: move integer-pointer cast hacks into backend) - rust-lang/rust#144545 (In rustc_pattern_analysis, put `true` witnesses before `false` witnesses) - rust-lang/rust#144579 (Implement declarative (`macro_rules!`) attribute macros (RFC 3697)) - rust-lang/rust#144649 (Account for bare tuples and `Pin` methods in field searching logic) - rust-lang/rust#144775 (more strongly dissuade use of `skip_binder`) - rust-lang/rust#144987 (Enable f16 and f128 on targets that were fixed in LLVM21) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup of 8 pull requests Successful merges: - rust-lang#139451 (Add `target_env = "macabi"` and `target_env = "sim"`) - rust-lang#144039 (Use `tcx.short_string()` in more diagnostics) - rust-lang#144192 (atomicrmw on pointers: move integer-pointer cast hacks into backend) - rust-lang#144545 (In rustc_pattern_analysis, put `true` witnesses before `false` witnesses) - rust-lang#144579 (Implement declarative (`macro_rules!`) attribute macros (RFC 3697)) - rust-lang#144649 (Account for bare tuples and `Pin` methods in field searching logic) - rust-lang#144775 (more strongly dissuade use of `skip_binder`) - rust-lang#144987 (Enable f16 and f128 on targets that were fixed in LLVM21) r? `@ghost` `@rustbot` modify labels: rollup
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People unfortunately encounter
BinderandEarlyBindervery early on when starting out. In these cases its often very easy to useskip_binderincorrectly. This makes it more explicit that it should generally not be used and points to the relevantrustc-dev-guidechapters.r? @BoxyUwU