Remove in-band lifetimes

2 files changed, 2 insertions, 79 deletions

diff --git a/compiler/rustc_resolve/src/late/diagnostics.rs b/compiler/rustc_resolve/src/late/diagnostics.rs
index f20cf29cc89..260fc81500a 100644
--- a/compiler/rustc_resolve/src/late/diagnostics.rs
+++ b/compiler/rustc_resolve/src/late/diagnostics.rs
@@ -1844,7 +1844,6 @@ impl<'tcx> LifetimeContext<'_, 'tcx> {
             lifetime_ref
         );
         err.span_label(lifetime_ref.span, "undeclared lifetime");
-        let mut suggests_in_band = false;
         let mut suggested_spans = vec![];
         for missing in &self.missing_named_lifetime_spots {
             match missing {
@@ -1860,7 +1859,6 @@ impl<'tcx> LifetimeContext<'_, 'tcx> {
                     }) {
                         (param.span.shrink_to_lo(), format!("{}, ", lifetime_ref))
                     } else {
-                        suggests_in_band = true;
                         (generics.span, format!("<{}>", lifetime_ref))
                     };
                     if suggested_spans.contains(&span) {
@@ -1895,15 +1893,6 @@ impl<'tcx> LifetimeContext<'_, 'tcx> {
                 _ => {}
             }
         }
-        if self.tcx.sess.is_nightly_build()
-            && !self.tcx.features().in_band_lifetimes
-            && suggests_in_band
-        {
-            err.help(
-                "if you want to experiment with in-band lifetime bindings, \
-                 add `#![feature(in_band_lifetimes)]` to the crate attributes",
-            );
-        }
         err.emit();
     }
 
diff --git a/compiler/rustc_resolve/src/late/lifetimes.rs b/compiler/rustc_resolve/src/late/lifetimes.rs
index 2f0ad60709d..aa25304992b 100644
--- a/compiler/rustc_resolve/src/late/lifetimes.rs
+++ b/compiler/rustc_resolve/src/late/lifetimes.rs
@@ -16,7 +16,7 @@ use rustc_hir::def_id::{DefIdMap, LocalDefId};
 use rustc_hir::hir_id::ItemLocalId;
 use rustc_hir::intravisit::{self, Visitor};
 use rustc_hir::{GenericArg, GenericParam, LifetimeName, Node, ParamName, QPath};
-use rustc_hir::{GenericParamKind, HirIdMap, HirIdSet, LifetimeParamKind};
+use rustc_hir::{GenericParamKind, HirIdMap, HirIdSet};
 use rustc_middle::hir::map::Map;
 use rustc_middle::hir::nested_filter;
 use rustc_middle::middle::resolve_lifetime::*;
@@ -1325,9 +1325,6 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
     }
 
     fn visit_generics(&mut self, generics: &'tcx hir::Generics<'tcx>) {
-        if !self.trait_definition_only {
-            check_mixed_explicit_and_in_band_defs(self.tcx, &generics.params);
-        }
         let scope = Scope::TraitRefBoundary { s: self.scope };
         self.with(scope, |_, this| {
             for param in generics.params {
@@ -1535,30 +1532,6 @@ impl ShadowKind {
     }
 }
 
-fn check_mixed_explicit_and_in_band_defs(tcx: TyCtxt<'_>, params: &[hir::GenericParam<'_>]) {
-    let lifetime_params: Vec<_> = params
-        .iter()
-        .filter_map(|param| match param.kind {
-            GenericParamKind::Lifetime { kind, .. } => Some((kind, param.span)),
-            _ => None,
-        })
-        .collect();
-    let explicit = lifetime_params.iter().find(|(kind, _)| *kind == LifetimeParamKind::Explicit);
-    let in_band = lifetime_params.iter().find(|(kind, _)| *kind == LifetimeParamKind::InBand);
-
-    if let (Some((_, explicit_span)), Some((_, in_band_span))) = (explicit, in_band) {
-        struct_span_err!(
-            tcx.sess,
-            *in_band_span,
-            E0688,
-            "cannot mix in-band and explicit lifetime definitions"
-        )
-        .span_label(*in_band_span, "in-band lifetime definition here")
-        .span_label(*explicit_span, "explicit lifetime definition here")
-        .emit();
-    }
-}
-
 fn signal_shadowing_problem(tcx: TyCtxt<'_>, name: Symbol, orig: Original, shadower: Shadower) {
     let mut err = if let (ShadowKind::Lifetime, ShadowKind::Lifetime) = (orig.kind, shadower.kind) {
         // lifetime/lifetime shadowing is an error
@@ -1845,13 +1818,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
     fn lifetime_deletion_span(&self, name: Ident, generics: &hir::Generics<'_>) -> Option<Span> {
         generics.params.iter().enumerate().find_map(|(i, param)| {
             if param.name.ident() == name {
-                let in_band = matches!(
-                    param.kind,
-                    hir::GenericParamKind::Lifetime { kind: hir::LifetimeParamKind::InBand }
-                );
-                if in_band {
-                    Some(param.span)
-                } else if generics.params.len() == 1 {
+                if generics.params.len() == 1 {
                     // if sole lifetime, remove the entire `<>` brackets
                     Some(generics.span)
                 } else {
@@ -2337,39 +2304,6 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
                 }
             }
 
-            // Check for fn-syntax conflicts with in-band lifetime definitions
-            if !self.trait_definition_only && self.is_in_fn_syntax {
-                match def {
-                    Region::EarlyBound(_, _, LifetimeDefOrigin::InBand)
-                    | Region::LateBound(_, _, _, LifetimeDefOrigin::InBand) => {
-                        struct_span_err!(
-                            self.tcx.sess,
-                            lifetime_ref.span,
-                            E0687,
-                            "lifetimes used in `fn` or `Fn` syntax must be \
-                             explicitly declared using `<...>` binders"
-                        )
-                        .span_label(lifetime_ref.span, "in-band lifetime definition")
-                        .emit();
-                    }
-
-                    Region::Static
-                    | Region::EarlyBound(
-                        _,
-                        _,
-                        LifetimeDefOrigin::ExplicitOrElided | LifetimeDefOrigin::Error,
-                    )
-                    | Region::LateBound(
-                        _,
-                        _,
-                        _,
-                        LifetimeDefOrigin::ExplicitOrElided | LifetimeDefOrigin::Error,
-                    )
-                    | Region::LateBoundAnon(..)
-                    | Region::Free(..) => {}
-                }
-            }
-
             self.insert_lifetime(lifetime_ref, def);
         } else {
             self.emit_undeclared_lifetime_error(lifetime_ref);