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Merge pull request #920 from ehuss/fix-generic-params
Update grammar for order of parameters/arguments.
2 parents 448002d + 9d0aa17 commit f8c39fe

11 files changed

+41
-63
lines changed

‎src/items/associated-items.md

+2-2
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@@ -80,7 +80,7 @@ let _: f64 = f64::from_i32(42);
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### Methods
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> _Method_ :\
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> &nbsp;&nbsp; [_FunctionQualifiers_] `fn` [IDENTIFIER]&nbsp;[_Generics_]<sup>?</sup>\
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> &nbsp;&nbsp; [_FunctionQualifiers_] `fn` [IDENTIFIER]&nbsp;[_GenericParams_]<sup>?</sup>\
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> &nbsp;&nbsp; &nbsp;&nbsp; `(` _SelfParam_ (`,` [_FunctionParam_])<sup>\*</sup> `,`<sup>?</sup> `)`\
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> &nbsp;&nbsp; &nbsp;&nbsp; [_FunctionReturnType_]<sup>?</sup> [_WhereClause_]<sup>?</sup>\
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> &nbsp;&nbsp; &nbsp;&nbsp; [_BlockExpression_]
@@ -344,7 +344,7 @@ fn main() {
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[_FunctionParam_]: functions.md
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[_FunctionQualifiers_]: functions.md
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[_FunctionReturnType_]: functions.md
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[_Generics_]: generics.md
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[_GenericParams_]: generics.md
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[_Lifetime_]: ../trait-bounds.md
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[_Type_]: ../types.md#type-expressions
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[_WhereClause_]: generics.md#where-clauses

‎src/items/enumerations.md

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@@ -4,7 +4,7 @@
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> _Enumeration_ :\
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> &nbsp;&nbsp; `enum`
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> [IDENTIFIER]&nbsp;
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> [_Generics_]<sup>?</sup>
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> [_GenericParams_]<sup>?</sup>
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> [_WhereClause_]<sup>?</sup>
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> `{` _EnumItems_<sup>?</sup> `}`
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>
@@ -172,7 +172,7 @@ enum E {
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```
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[IDENTIFIER]: ../identifiers.md
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[_Generics_]: generics.md
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[_GenericParams_]: generics.md
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[_WhereClause_]: generics.md#where-clauses
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[_Expression_]: ../expressions.md
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[_TupleFields_]: structs.md

‎src/items/external-blocks.md

+2-2
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@@ -17,7 +17,7 @@
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> &nbsp;&nbsp; `static` `mut`<sup>?</sup> [IDENTIFIER] `:` [_Type_] `;`
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>
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> _ExternalFunctionItem_ :\
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> &nbsp;&nbsp; `fn` [IDENTIFIER]&nbsp;[_Generics_]<sup>?</sup>\
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> &nbsp;&nbsp; `fn` [IDENTIFIER]&nbsp;[_GenericParams_]<sup>?</sup>\
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> &nbsp;&nbsp; `(` ( _NamedFunctionParameters_ | _NamedFunctionParametersWithVariadics_ )<sup>?</sup> `)`\
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> &nbsp;&nbsp; [_FunctionReturnType_]<sup>?</sup> [_WhereClause_]<sup>?</sup> `;`
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>
@@ -190,7 +190,7 @@ restrictions as [regular function parameters].
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[statics]: static-items.md
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[_Abi_]: functions.md
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[_FunctionReturnType_]: functions.md
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[_Generics_]: generics.md
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[_GenericParams_]: generics.md
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[_InnerAttribute_]: ../attributes.md
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[_MacroInvocationSemi_]: ../macros.md#macro-invocation
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[_MetaListNameValueStr_]: ../attributes.md#meta-item-attribute-syntax

‎src/items/functions.md

+2-2
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@@ -2,7 +2,7 @@
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> **<sup>Syntax</sup>**\
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> _Function_ :\
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> &nbsp;&nbsp; _FunctionQualifiers_ `fn` [IDENTIFIER]&nbsp;[_Generics_]<sup>?</sup>\
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> &nbsp;&nbsp; _FunctionQualifiers_ `fn` [IDENTIFIER]&nbsp;[_GenericParams_]<sup>?</sup>\
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> &nbsp;&nbsp; &nbsp;&nbsp; `(` _FunctionParameters_<sup>?</sup> `)`\
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> &nbsp;&nbsp; &nbsp;&nbsp; _FunctionReturnType_<sup>?</sup> [_WhereClause_]<sup>?</sup>\
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> &nbsp;&nbsp; &nbsp;&nbsp; [_BlockExpression_]
@@ -341,7 +341,7 @@ fn foo_oof(#[some_inert_attribute] arg: u8) {
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[RAW_STRING_LITERAL]: ../tokens.md#raw-string-literals
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[STRING_LITERAL]: ../tokens.md#string-literals
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[_BlockExpression_]: ../expressions/block-expr.md
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[_Generics_]: generics.md
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[_GenericParams_]: generics.md
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[_Pattern_]: ../patterns.md
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[_Type_]: ../types.md#type-expressions
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[_WhereClause_]: generics.md#where-clauses

‎src/items/generics.md

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@@ -1,31 +1,21 @@
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# Generic parameters
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> **<sup>Syntax</sup>**\
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> _Generics_ :\
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> &nbsp;&nbsp; `<` _GenericParams_ `>`
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>
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> _GenericParams_ :\
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> &nbsp;&nbsp; &nbsp;&nbsp; _LifetimeParams_\
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> &nbsp;&nbsp; | ( _LifetimeParam_ `,` )<sup>\*</sup> _TypeParams_\
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> &nbsp;&nbsp; | ( _LifetimeParam_ `,` )<sup>\*</sup> ( _TypeParam_ `,` )<sup>\*</sup> _ConstParams_
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> &nbsp;&nbsp; &nbsp;&nbsp; `<` `>`\
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> &nbsp;&nbsp; | `<` (_GenericParam_ `,`)<sup>\*</sup> _GenericParam_ `,`<sup>?</sup> `>`
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>
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> _LifetimeParams_ :\
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> &nbsp;&nbsp; ( _LifetimeParam_ `,` )<sup>\*</sup> _LifetimeParam_<sup>?</sup>
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> _GenericParam_ :\
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> &nbsp;&nbsp; [_OuterAttribute_]<sup>\*</sup> ( _LifetimeParam_ | _TypeParam_ | _ConstParam_ )
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>
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> _LifetimeParam_ :\
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> &nbsp;&nbsp; [_OuterAttribute_]<sup>?</sup> [LIFETIME_OR_LABEL]&nbsp;( `:` [_LifetimeBounds_] )<sup>?</sup>
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>
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> _TypeParams_:\
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> &nbsp;&nbsp; ( _TypeParam_ `,` )<sup>\*</sup> _TypeParam_<sup>?</sup>
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> &nbsp;&nbsp; [LIFETIME_OR_LABEL]&nbsp;( `:` [_LifetimeBounds_] )<sup>?</sup>
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>
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> _TypeParam_ :\
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> &nbsp;&nbsp; [_OuterAttribute_]<sup>?</sup> [IDENTIFIER]( `:` [_TypeParamBounds_]<sup>?</sup> )<sup>?</sup> ( `=` [_Type_] )<sup>?</sup>
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>
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> _ConstParams_:\
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> &nbsp;&nbsp; ( _ConstParam_ `,` )<sup>\*</sup> _ConstParam_<sup>?</sup>
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> &nbsp;&nbsp; [IDENTIFIER]( `:` [_TypeParamBounds_]<sup>?</sup> )<sup>?</sup> ( `=` [_Type_] )<sup>?</sup>
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>
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> _ConstParam_:\
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> &nbsp;&nbsp; [_OuterAttribute_]<sup>?</sup> `const` [IDENTIFIER] `:` [_Type_]
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> &nbsp;&nbsp; `const` [IDENTIFIER] `:` [_Type_]
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Functions, type aliases, structs, enumerations, unions, traits, and
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implementations may be *parameterized* by types, constants, and lifetimes. These
@@ -91,12 +81,15 @@ referred to with path syntax.
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> &nbsp;&nbsp; _ForLifetimes_<sup>?</sup> [_Type_] `:` [_TypeParamBounds_]<sup>?</sup>
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>
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> _ForLifetimes_ :\
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> &nbsp;&nbsp; `for` `<` [_LifetimeParams_](#generic-parameters) `>`
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> &nbsp;&nbsp; `for` [_GenericParams_](#generic-parameters)
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*Where clauses* provide another way to specify bounds on type and lifetime
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parameters as well as a way to specify bounds on types that aren't type
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parameters.
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The `for` keyword can be used to introduce [higher-ranked lifetimes]. It only
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allows [_LifetimeParam_] parameters.
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Bounds that don't use the item's parameters or higher-ranked lifetimes are
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checked when the item is defined. It is an error for such a bound to be false.
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@@ -141,6 +134,7 @@ struct Foo<#[my_flexible_clone(unbounded)] H> {
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[IDENTIFIER]: ../identifiers.md
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[LIFETIME_OR_LABEL]: ../tokens.md#lifetimes-and-loop-labels
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[_LifetimeParam_]: #generic-parameters
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[_LifetimeBounds_]: ../trait-bounds.md
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[_Lifetime_]: ../trait-bounds.md
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[_OuterAttribute_]: ../attributes.md
@@ -150,6 +144,7 @@ struct Foo<#[my_flexible_clone(unbounded)] H> {
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[arrays]: ../types/array.md
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[const contexts]: ../const_eval.md#const-context
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[function pointers]: ../types/function-pointer.md
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[higher-ranked lifetimes]: ../trait-bounds.md#higher-ranked-trait-bounds
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[raw pointers]: ../types/pointer.md#raw-pointers-const-and-mut
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[references]: ../types/pointer.md#shared-references-
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[repeat expressions]: ../expressions/array-expr.md

‎src/items/implementations.md

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@@ -5,7 +5,7 @@
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> &nbsp;&nbsp; _InherentImpl_ | _TraitImpl_
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>
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> _InherentImpl_ :\
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> &nbsp;&nbsp; `impl` [_Generics_]<sup>?</sup>&nbsp;[_Type_]&nbsp;[_WhereClause_]<sup>?</sup> `{`\
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> &nbsp;&nbsp; `impl` [_GenericParams_]<sup>?</sup>&nbsp;[_Type_]&nbsp;[_WhereClause_]<sup>?</sup> `{`\
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> &nbsp;&nbsp; &nbsp;&nbsp; [_InnerAttribute_]<sup>\*</sup>\
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> &nbsp;&nbsp; &nbsp;&nbsp; _InherentImplItem_<sup>\*</sup>\
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> &nbsp;&nbsp; `}`
@@ -17,7 +17,7 @@
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> &nbsp;&nbsp; )
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>
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> _TraitImpl_ :\
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> &nbsp;&nbsp; `unsafe`<sup>?</sup> `impl` [_Generics_]<sup>?</sup> `!`<sup>?</sup>
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> &nbsp;&nbsp; `unsafe`<sup>?</sup> `impl` [_GenericParams_]<sup>?</sup> `!`<sup>?</sup>
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> [_TypePath_] `for` [_Type_]\
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> &nbsp;&nbsp; [_WhereClause_]<sup>?</sup>\
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> &nbsp;&nbsp; `{`\
@@ -206,7 +206,7 @@ attributes].
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[_ConstantItem_]: constant-items.md
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[_Function_]: functions.md
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[_Generics_]: generics.md
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[_GenericParams_]: generics.md
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[_InnerAttribute_]: ../attributes.md
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[_MacroInvocationSemi_]: ../macros.md#macro-invocation
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[_Method_]: associated-items.md#methods

‎src/items/structs.md

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@@ -8,14 +8,14 @@
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> _StructStruct_ :\
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> &nbsp;&nbsp; `struct`
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> [IDENTIFIER]&nbsp;
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> [_Generics_]<sup>?</sup>
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> [_GenericParams_]<sup>?</sup>
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> [_WhereClause_]<sup>?</sup>
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> ( `{` _StructFields_<sup>?</sup> `}` | `;` )
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>
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> _TupleStruct_ :\
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> &nbsp;&nbsp; `struct`
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> [IDENTIFIER]&nbsp;
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> [_Generics_]<sup>?</sup>
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> [_GenericParams_]<sup>?</sup>
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> `(` _TupleFields_<sup>?</sup> `)`
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> [_WhereClause_]<sup>?</sup>
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> `;`
@@ -82,7 +82,7 @@ particular layout using the [`repr` attribute].
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[_OuterAttribute_]: ../attributes.md
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[IDENTIFIER]: ../identifiers.md
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[_Generics_]: generics.md
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[_GenericParams_]: generics.md
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[_WhereClause_]: generics.md#where-clauses
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[_Visibility_]: ../visibility-and-privacy.md
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[_Type_]: ../types.md#type-expressions

‎src/items/traits.md

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> **<sup>Syntax</sup>**\
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> _Trait_ :\
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> &nbsp;&nbsp; `unsafe`<sup>?</sup> `trait` [IDENTIFIER]&nbsp;
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> [_Generics_]<sup>?</sup>
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> [_GenericParams_]<sup>?</sup>
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> ( `:` [_TypeParamBounds_]<sup>?</sup> )<sup>?</sup>
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> [_WhereClause_]<sup>?</sup> `{`\
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> &nbsp;&nbsp;&nbsp;&nbsp; [_InnerAttribute_]<sup>\*</sup>\
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> &nbsp;&nbsp; &nbsp;&nbsp; _TraitMethodDecl_ ( `;` | [_BlockExpression_] )
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>
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> _TraitFunctionDecl_ :\
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> &nbsp;&nbsp; [_FunctionQualifiers_] `fn` [IDENTIFIER]&nbsp;[_Generics_]<sup>?</sup>\
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> &nbsp;&nbsp; [_FunctionQualifiers_] `fn` [IDENTIFIER]&nbsp;[_GenericParams_]<sup>?</sup>\
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> &nbsp;&nbsp; &nbsp;&nbsp; `(` _TraitFunctionParameters_<sup>?</sup> `)`\
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> &nbsp;&nbsp; &nbsp;&nbsp; [_FunctionReturnType_]<sup>?</sup> [_WhereClause_]<sup>?</sup>
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>
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> _TraitMethodDecl_ :\
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> &nbsp;&nbsp; [_FunctionQualifiers_] `fn` [IDENTIFIER]&nbsp;[_Generics_]<sup>?</sup>\
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> &nbsp;&nbsp; [_FunctionQualifiers_] `fn` [IDENTIFIER]&nbsp;[_GenericParams_]<sup>?</sup>\
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> &nbsp;&nbsp; &nbsp;&nbsp; `(` [_SelfParam_] (`,` _TraitFunctionParam_)<sup>\*</sup> `,`<sup>?</sup> `)`\
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> &nbsp;&nbsp; &nbsp;&nbsp; [_FunctionReturnType_]<sup>?</sup> [_WhereClause_]<sup>?</sup>
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>
@@ -339,7 +339,7 @@ fn main() {
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[_Expression_]: ../expressions.md
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[_FunctionQualifiers_]: functions.md
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[_FunctionReturnType_]: functions.md
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[_Generics_]: generics.md
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[_GenericParams_]: generics.md
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[_MacroInvocationSemi_]: ../macros.md#macro-invocation
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[_OuterAttribute_]: ../attributes.md
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[_InnerAttribute_]: ../attributes.md

‎src/items/type-aliases.md

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> **<sup>Syntax</sup>**\
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> _TypeAlias_ :\
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> &nbsp;&nbsp; `type` [IDENTIFIER]&nbsp;[_Generics_]<sup>?</sup>
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> &nbsp;&nbsp; `type` [IDENTIFIER]&nbsp;[_GenericParams_]<sup>?</sup>
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> [_WhereClause_]<sup>?</sup> `=` [_Type_] `;`
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A _type alias_ defines a new name for an existing [type]. Type aliases are
@@ -33,6 +33,6 @@ let _ = TypeAlias(5); // Doesn't work
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```
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[IDENTIFIER]: ../identifiers.md
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[_Generics_]: generics.md
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[_GenericParams_]: generics.md
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[_WhereClause_]: generics.md#where-clauses
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[_Type_]: ../types.md#type-expressions

‎src/items/unions.md

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> **<sup>Syntax</sup>**\
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> _Union_ :\
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> &nbsp;&nbsp; `union` [IDENTIFIER]&nbsp;[_Generics_]<sup>?</sup> [_WhereClause_]<sup>?</sup>
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> &nbsp;&nbsp; `union` [IDENTIFIER]&nbsp;[_GenericParams_]<sup>?</sup> [_WhereClause_]<sup>?</sup>
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> `{`[_StructFields_] `}`
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A union declaration uses the same syntax as a struct declaration, except with
@@ -177,7 +177,7 @@ generics, trait implementations, inherent implementations, coherence, pattern
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checking, etc etc etc).
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[IDENTIFIER]: ../identifiers.md
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[_Generics_]: generics.md
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[_GenericParams_]: generics.md
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[_WhereClause_]: generics.md#where-clauses
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[_StructFields_]: structs.md
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[`transmute`]: ../../std/mem/fn.transmute.html

‎src/paths.md

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@@ -50,37 +50,17 @@ mod m {
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>
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> _GenericArgs_ :\
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> &nbsp;&nbsp; &nbsp;&nbsp; `<` `>`\
53-
> &nbsp;&nbsp; | `<` _GenericArgsLifetimes_ `,`<sup>?</sup> `>`\
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> &nbsp;&nbsp; | `<` _GenericArgsTypes_ `,`<sup>?</sup> `>`\
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> &nbsp;&nbsp; | `<` _GenericArgsConsts_ `,`<sup>?</sup> `>`\
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> &nbsp;&nbsp; | `<` _GenericArgsBindings_ `,`<sup>?</sup> `>`\
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> &nbsp;&nbsp; | `<` _GenericArgsLifetimes_ `,` _GenericArgsTypes_ `,`<sup>?</sup> `>`\
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> &nbsp;&nbsp; | `<` _GenericArgsLifetimes_ `,` _GenericArgsConsts_ `,`<sup>?</sup> `>`\
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> &nbsp;&nbsp; | `<` _GenericArgsLifetimes_ `,` _GenericArgsBindings_ `,`<sup>?</sup> `>`\
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> &nbsp;&nbsp; | `<` _GenericArgsLifetimes_ `,` _GenericArgsTypes_ `,` _GenericArgsConsts_ `,`<sup>?</sup> `>`\
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> &nbsp;&nbsp; | `<` _GenericArgsLifetimes_ `,` _GenericArgsTypes_ `,` _GenericArgsBindings_ `,`<sup>?</sup> `>`\
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> &nbsp;&nbsp; | `<` _GenericArgsLifetimes_ `,` _GenericArgsConsts_ `,` _GenericArgsBindings_ `,`<sup>?</sup> `>`\
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> &nbsp;&nbsp; | `<` _GenericArgsTypes_ `,` _GenericArgsConsts_ `,` _GenericArgsBindings_ `,`<sup>?</sup> `>`\
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> &nbsp;&nbsp; | `<` _GenericArgsLifetimes_ `,` _GenericArgsTypes_ `,` _GenericArgsConsts_ `,` _GenericArgsBindings_ `,`<sup>?</sup> `>`
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> &nbsp;&nbsp; | `<` ( _GenericArg_ `,` )<sup>\*</sup> _GenericArg_ `,`<sup>?</sup> `>`
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>
66-
> _GenericArgsLifetimes_ :\
67-
> &nbsp;&nbsp; [_Lifetime_] (`,` [_Lifetime_])<sup>\*</sup>
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>
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> _GenericArgsTypes_ :\
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> &nbsp;&nbsp; [_Type_] (`,` [_Type_])<sup>\*</sup>
71-
>
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> _GenericArgsConsts_ :\
73-
> &nbsp;&nbsp; _GenericArgsConst_ (`,` _GenericArgsConst_)<sup>\*</sup>
55+
> _GenericArg_ :\
56+
> &nbsp;&nbsp; [_Lifetime_] | [_Type_] | _GenericArgsConst_ | _GenericArgsBinding_
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>
7558
> _GenericArgsConst_ :\
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> &nbsp;&nbsp; &nbsp;&nbsp; [_BlockExpression_]\
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> &nbsp;&nbsp; | [_LiteralExpression_]\
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> &nbsp;&nbsp; | `-` [_LiteralExpression_]\
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> &nbsp;&nbsp; | [_SimplePathSegment_]
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>
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> _GenericArgsBindings_ :\
82-
> &nbsp;&nbsp; _GenericArgsBinding_ (`,` _GenericArgsBinding_)<sup>\*</sup>
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>
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> _GenericArgsBinding_ :\
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> &nbsp;&nbsp; [IDENTIFIER] `=` [_Type_]
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@@ -95,6 +75,9 @@ ambiguity with the less-than operator. This is colloquially known as "turbofish"
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Vec::<u8>::with_capacity(1024);
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```
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The order of generic arguments is restricted to lifetime arguments, then type
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arguments, then const arguments, then equality constraints.
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Const arguments must be surrounded by braces unless they are a
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[literal] or a single segment path.
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