Update lifetimes for pre-expansion validation

Author: ehuss

src/items/generics.md

@@ -9,7 +9,7 @@
 > &nbsp;&nbsp; [_OuterAttribute_]<sup>\*</sup> ( _LifetimeParam_ | _TypeParam_ | _ConstParam_ )
 >
 > _LifetimeParam_ :\
-> &nbsp;&nbsp; [LIFETIME_OR_LABEL]&nbsp;( `:` [_LifetimeBounds_] )<sup>?</sup>
+> &nbsp;&nbsp; [_Lifetime_]&nbsp;( `:` [_LifetimeBounds_] )<sup>?</sup>
 >
 > _TypeParam_ :\
 > &nbsp;&nbsp; [IDENTIFIER]&nbsp;( `:` [_TypeParamBounds_]<sup>?</sup> )<sup>?</sup> ( `=` [_Type_] )<sup>?</sup>
@@ -44,7 +44,7 @@ See [generic parameter scopes] for more details.
 [function pointers] have lifetime or type parameters as well, but are not
 referred to with path syntax.
 
-`'_` is not a valid lifetime parameter.
+`'_` and `'_static` are not valid lifetime parameters.
 
 ### Const generics
 
@@ -263,7 +263,6 @@ struct Foo<#[my_flexible_clone(unbounded)] H> {
 ```
 
 [IDENTIFIER]: ../identifiers.md
-[LIFETIME_OR_LABEL]: ../tokens.md#lifetimes-and-loop-labels
 
 [_ForLifetimes_]: ../trait-bounds.md#higher-ranked-trait-bounds
 [_LifetimeParam_]: #generic-parameters

src/tokens.md

@@ -762,8 +762,6 @@ r[lex.token.life.syntax]
 >
 > LIFETIME_OR_LABEL :\
 >       `'` [NON_KEYWORD_IDENTIFIER][identifier]
->   _(not immediately followed by `'`)_\
->    | `'_`
 >   _(not immediately followed by `'`)_
 
 r[lex.token.life.intro]

src/trait-bounds.md

@@ -21,7 +21,8 @@ r[bound.syntax]
 >
 > _Lifetime_ :\
 >       [LIFETIME_OR_LABEL]\
->    | `'static`
+>    | `'static`\
+>    | `'_`
 >
 > _UseBound_ :\
 >    `use` _UseBoundGenericArgs_