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Update grammar for order of parameters/arguments. #920

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4 changes: 2 additions & 2 deletions src/items/associated-items.md
Original file line number Diff line number Diff line change
Expand Up @@ -80,7 +80,7 @@ let _: f64 = f64::from_i32(42);
### Methods

> _Method_ :\
> &nbsp;&nbsp; [_FunctionQualifiers_] `fn` [IDENTIFIER]&nbsp;[_Generics_]<sup>?</sup>\
> &nbsp;&nbsp; [_FunctionQualifiers_] `fn` [IDENTIFIER]&nbsp;[_GenericParams_]<sup>?</sup>\
> &nbsp;&nbsp; &nbsp;&nbsp; `(` _SelfParam_ (`,` [_FunctionParam_])<sup>\*</sup> `,`<sup>?</sup> `)`\
> &nbsp;&nbsp; &nbsp;&nbsp; [_FunctionReturnType_]<sup>?</sup> [_WhereClause_]<sup>?</sup>\
> &nbsp;&nbsp; &nbsp;&nbsp; [_BlockExpression_]
Expand Down Expand Up @@ -344,7 +344,7 @@ fn main() {
[_FunctionParam_]: functions.md
[_FunctionQualifiers_]: functions.md
[_FunctionReturnType_]: functions.md
[_Generics_]: generics.md
[_GenericParams_]: generics.md
[_Lifetime_]: ../trait-bounds.md
[_Type_]: ../types.md#type-expressions
[_WhereClause_]: generics.md#where-clauses
Expand Down
4 changes: 2 additions & 2 deletions src/items/enumerations.md
Original file line number Diff line number Diff line change
Expand Up @@ -4,7 +4,7 @@
> _Enumeration_ :\
> &nbsp;&nbsp; `enum`
> [IDENTIFIER]&nbsp;
> [_Generics_]<sup>?</sup>
> [_GenericParams_]<sup>?</sup>
> [_WhereClause_]<sup>?</sup>
> `{` _EnumItems_<sup>?</sup> `}`
>
Expand Down Expand Up @@ -172,7 +172,7 @@ enum E {
```

[IDENTIFIER]: ../identifiers.md
[_Generics_]: generics.md
[_GenericParams_]: generics.md
[_WhereClause_]: generics.md#where-clauses
[_Expression_]: ../expressions.md
[_TupleFields_]: structs.md
Expand Down
4 changes: 2 additions & 2 deletions src/items/external-blocks.md
Original file line number Diff line number Diff line change
Expand Up @@ -17,7 +17,7 @@
> &nbsp;&nbsp; `static` `mut`<sup>?</sup> [IDENTIFIER] `:` [_Type_] `;`
>
> _ExternalFunctionItem_ :\
> &nbsp;&nbsp; `fn` [IDENTIFIER]&nbsp;[_Generics_]<sup>?</sup>\
> &nbsp;&nbsp; `fn` [IDENTIFIER]&nbsp;[_GenericParams_]<sup>?</sup>\
> &nbsp;&nbsp; `(` ( _NamedFunctionParameters_ | _NamedFunctionParametersWithVariadics_ )<sup>?</sup> `)`\
> &nbsp;&nbsp; [_FunctionReturnType_]<sup>?</sup> [_WhereClause_]<sup>?</sup> `;`
>
Expand Down Expand Up @@ -190,7 +190,7 @@ restrictions as [regular function parameters].
[statics]: static-items.md
[_Abi_]: functions.md
[_FunctionReturnType_]: functions.md
[_Generics_]: generics.md
[_GenericParams_]: generics.md
[_InnerAttribute_]: ../attributes.md
[_MacroInvocationSemi_]: ../macros.md#macro-invocation
[_MetaListNameValueStr_]: ../attributes.md#meta-item-attribute-syntax
Expand Down
4 changes: 2 additions & 2 deletions src/items/functions.md
Original file line number Diff line number Diff line change
Expand Up @@ -2,7 +2,7 @@

> **<sup>Syntax</sup>**\
> _Function_ :\
> &nbsp;&nbsp; _FunctionQualifiers_ `fn` [IDENTIFIER]&nbsp;[_Generics_]<sup>?</sup>\
> &nbsp;&nbsp; _FunctionQualifiers_ `fn` [IDENTIFIER]&nbsp;[_GenericParams_]<sup>?</sup>\
> &nbsp;&nbsp; &nbsp;&nbsp; `(` _FunctionParameters_<sup>?</sup> `)`\
> &nbsp;&nbsp; &nbsp;&nbsp; _FunctionReturnType_<sup>?</sup> [_WhereClause_]<sup>?</sup>\
> &nbsp;&nbsp; &nbsp;&nbsp; [_BlockExpression_]
Expand Down Expand Up @@ -341,7 +341,7 @@ fn foo_oof(#[some_inert_attribute] arg: u8) {
[RAW_STRING_LITERAL]: ../tokens.md#raw-string-literals
[STRING_LITERAL]: ../tokens.md#string-literals
[_BlockExpression_]: ../expressions/block-expr.md
[_Generics_]: generics.md
[_GenericParams_]: generics.md
[_Pattern_]: ../patterns.md
[_Type_]: ../types.md#type-expressions
[_WhereClause_]: generics.md#where-clauses
Expand Down
31 changes: 13 additions & 18 deletions src/items/generics.md
Original file line number Diff line number Diff line change
@@ -1,31 +1,21 @@
# Generic parameters

> **<sup>Syntax</sup>**\
> _Generics_ :\
> &nbsp;&nbsp; `<` _GenericParams_ `>`
>
> _GenericParams_ :\
> &nbsp;&nbsp; &nbsp;&nbsp; _LifetimeParams_\
> &nbsp;&nbsp; | ( _LifetimeParam_ `,` )<sup>\*</sup> _TypeParams_\
> &nbsp;&nbsp; | ( _LifetimeParam_ `,` )<sup>\*</sup> ( _TypeParam_ `,` )<sup>\*</sup> _ConstParams_
> &nbsp;&nbsp; &nbsp;&nbsp; `<` `>`\
> &nbsp;&nbsp; | `<` (_GenericParam_ `,`)<sup>\*</sup> _GenericParam_ `,`<sup>?</sup> `>`
>
> _LifetimeParams_ :\
> &nbsp;&nbsp; ( _LifetimeParam_ `,` )<sup>\*</sup> _LifetimeParam_<sup>?</sup>
> _GenericParam_ :\
> &nbsp;&nbsp; [_OuterAttribute_]<sup>\*</sup> ( _LifetimeParam_ | _TypeParam_ | _ConstParam_ )
>
> _LifetimeParam_ :\
> &nbsp;&nbsp; [_OuterAttribute_]<sup>?</sup> [LIFETIME_OR_LABEL]&nbsp;( `:` [_LifetimeBounds_] )<sup>?</sup>
>
> _TypeParams_:\
> &nbsp;&nbsp; ( _TypeParam_ `,` )<sup>\*</sup> _TypeParam_<sup>?</sup>
> &nbsp;&nbsp; [LIFETIME_OR_LABEL]&nbsp;( `:` [_LifetimeBounds_] )<sup>?</sup>
>
> _TypeParam_ :\
> &nbsp;&nbsp; [_OuterAttribute_]<sup>?</sup> [IDENTIFIER]( `:` [_TypeParamBounds_]<sup>?</sup> )<sup>?</sup> ( `=` [_Type_] )<sup>?</sup>
>
> _ConstParams_:\
> &nbsp;&nbsp; ( _ConstParam_ `,` )<sup>\*</sup> _ConstParam_<sup>?</sup>
> &nbsp;&nbsp; [IDENTIFIER]( `:` [_TypeParamBounds_]<sup>?</sup> )<sup>?</sup> ( `=` [_Type_] )<sup>?</sup>
>
> _ConstParam_:\
> &nbsp;&nbsp; [_OuterAttribute_]<sup>?</sup> `const` [IDENTIFIER] `:` [_Type_]
> &nbsp;&nbsp; `const` [IDENTIFIER] `:` [_Type_]

Functions, type aliases, structs, enumerations, unions, traits, and
implementations may be *parameterized* by types, constants, and lifetimes. These
Expand Down Expand Up @@ -91,12 +81,15 @@ referred to with path syntax.
> &nbsp;&nbsp; _ForLifetimes_<sup>?</sup> [_Type_] `:` [_TypeParamBounds_]<sup>?</sup>
>
> _ForLifetimes_ :\
> &nbsp;&nbsp; `for` `<` [_LifetimeParams_](#generic-parameters) `>`
> &nbsp;&nbsp; `for` [_GenericParams_](#generic-parameters)

*Where clauses* provide another way to specify bounds on type and lifetime
parameters as well as a way to specify bounds on types that aren't type
parameters.

The `for` keyword can be used to introduce [higher-ranked lifetimes]. It only
allows [_LifetimeParam_] parameters.

Bounds that don't use the item's parameters or higher-ranked lifetimes are
checked when the item is defined. It is an error for such a bound to be false.

Expand Down Expand Up @@ -141,6 +134,7 @@ struct Foo<#[my_flexible_clone(unbounded)] H> {
[IDENTIFIER]: ../identifiers.md
[LIFETIME_OR_LABEL]: ../tokens.md#lifetimes-and-loop-labels

[_LifetimeParam_]: #generic-parameters
[_LifetimeBounds_]: ../trait-bounds.md
[_Lifetime_]: ../trait-bounds.md
[_OuterAttribute_]: ../attributes.md
Expand All @@ -150,6 +144,7 @@ struct Foo<#[my_flexible_clone(unbounded)] H> {
[arrays]: ../types/array.md
[const contexts]: ../const_eval.md#const-context
[function pointers]: ../types/function-pointer.md
[higher-ranked lifetimes]: ../trait-bounds.md#higher-ranked-trait-bounds
[raw pointers]: ../types/pointer.md#raw-pointers-const-and-mut
[references]: ../types/pointer.md#shared-references-
[repeat expressions]: ../expressions/array-expr.md
Expand Down
6 changes: 3 additions & 3 deletions src/items/implementations.md
Original file line number Diff line number Diff line change
Expand Up @@ -5,7 +5,7 @@
> &nbsp;&nbsp; _InherentImpl_ | _TraitImpl_
>
> _InherentImpl_ :\
> &nbsp;&nbsp; `impl` [_Generics_]<sup>?</sup>&nbsp;[_Type_]&nbsp;[_WhereClause_]<sup>?</sup> `{`\
> &nbsp;&nbsp; `impl` [_GenericParams_]<sup>?</sup>&nbsp;[_Type_]&nbsp;[_WhereClause_]<sup>?</sup> `{`\
> &nbsp;&nbsp; &nbsp;&nbsp; [_InnerAttribute_]<sup>\*</sup>\
> &nbsp;&nbsp; &nbsp;&nbsp; _InherentImplItem_<sup>\*</sup>\
> &nbsp;&nbsp; `}`
Expand All @@ -17,7 +17,7 @@
> &nbsp;&nbsp; )
>
> _TraitImpl_ :\
> &nbsp;&nbsp; `unsafe`<sup>?</sup> `impl` [_Generics_]<sup>?</sup> `!`<sup>?</sup>
> &nbsp;&nbsp; `unsafe`<sup>?</sup> `impl` [_GenericParams_]<sup>?</sup> `!`<sup>?</sup>
> [_TypePath_] `for` [_Type_]\
> &nbsp;&nbsp; [_WhereClause_]<sup>?</sup>\
> &nbsp;&nbsp; `{`\
Expand Down Expand Up @@ -206,7 +206,7 @@ attributes].

[_ConstantItem_]: constant-items.md
[_Function_]: functions.md
[_Generics_]: generics.md
[_GenericParams_]: generics.md
[_InnerAttribute_]: ../attributes.md
[_MacroInvocationSemi_]: ../macros.md#macro-invocation
[_Method_]: associated-items.md#methods
Expand Down
6 changes: 3 additions & 3 deletions src/items/structs.md
Original file line number Diff line number Diff line change
Expand Up @@ -8,14 +8,14 @@
> _StructStruct_ :\
> &nbsp;&nbsp; `struct`
> [IDENTIFIER]&nbsp;
> [_Generics_]<sup>?</sup>
> [_GenericParams_]<sup>?</sup>
> [_WhereClause_]<sup>?</sup>
> ( `{` _StructFields_<sup>?</sup> `}` | `;` )
>
> _TupleStruct_ :\
> &nbsp;&nbsp; `struct`
> [IDENTIFIER]&nbsp;
> [_Generics_]<sup>?</sup>
> [_GenericParams_]<sup>?</sup>
> `(` _TupleFields_<sup>?</sup> `)`
> [_WhereClause_]<sup>?</sup>
> `;`
Expand Down Expand Up @@ -82,7 +82,7 @@ particular layout using the [`repr` attribute].

[_OuterAttribute_]: ../attributes.md
[IDENTIFIER]: ../identifiers.md
[_Generics_]: generics.md
[_GenericParams_]: generics.md
[_WhereClause_]: generics.md#where-clauses
[_Visibility_]: ../visibility-and-privacy.md
[_Type_]: ../types.md#type-expressions
8 changes: 4 additions & 4 deletions src/items/traits.md
Original file line number Diff line number Diff line change
Expand Up @@ -3,7 +3,7 @@
> **<sup>Syntax</sup>**\
> _Trait_ :\
> &nbsp;&nbsp; `unsafe`<sup>?</sup> `trait` [IDENTIFIER]&nbsp;
> [_Generics_]<sup>?</sup>
> [_GenericParams_]<sup>?</sup>
> ( `:` [_TypeParamBounds_]<sup>?</sup> )<sup>?</sup>
> [_WhereClause_]<sup>?</sup> `{`\
> &nbsp;&nbsp;&nbsp;&nbsp; [_InnerAttribute_]<sup>\*</sup>\
Expand All @@ -26,12 +26,12 @@
> &nbsp;&nbsp; &nbsp;&nbsp; _TraitMethodDecl_ ( `;` | [_BlockExpression_] )
>
> _TraitFunctionDecl_ :\
> &nbsp;&nbsp; [_FunctionQualifiers_] `fn` [IDENTIFIER]&nbsp;[_Generics_]<sup>?</sup>\
> &nbsp;&nbsp; [_FunctionQualifiers_] `fn` [IDENTIFIER]&nbsp;[_GenericParams_]<sup>?</sup>\
> &nbsp;&nbsp; &nbsp;&nbsp; `(` _TraitFunctionParameters_<sup>?</sup> `)`\
> &nbsp;&nbsp; &nbsp;&nbsp; [_FunctionReturnType_]<sup>?</sup> [_WhereClause_]<sup>?</sup>
>
> _TraitMethodDecl_ :\
> &nbsp;&nbsp; [_FunctionQualifiers_] `fn` [IDENTIFIER]&nbsp;[_Generics_]<sup>?</sup>\
> &nbsp;&nbsp; [_FunctionQualifiers_] `fn` [IDENTIFIER]&nbsp;[_GenericParams_]<sup>?</sup>\
> &nbsp;&nbsp; &nbsp;&nbsp; `(` [_SelfParam_] (`,` _TraitFunctionParam_)<sup>\*</sup> `,`<sup>?</sup> `)`\
> &nbsp;&nbsp; &nbsp;&nbsp; [_FunctionReturnType_]<sup>?</sup> [_WhereClause_]<sup>?</sup>
>
Expand Down Expand Up @@ -339,7 +339,7 @@ fn main() {
[_Expression_]: ../expressions.md
[_FunctionQualifiers_]: functions.md
[_FunctionReturnType_]: functions.md
[_Generics_]: generics.md
[_GenericParams_]: generics.md
[_MacroInvocationSemi_]: ../macros.md#macro-invocation
[_OuterAttribute_]: ../attributes.md
[_InnerAttribute_]: ../attributes.md
Expand Down
4 changes: 2 additions & 2 deletions src/items/type-aliases.md
Original file line number Diff line number Diff line change
Expand Up @@ -2,7 +2,7 @@

> **<sup>Syntax</sup>**\
> _TypeAlias_ :\
> &nbsp;&nbsp; `type` [IDENTIFIER]&nbsp;[_Generics_]<sup>?</sup>
> &nbsp;&nbsp; `type` [IDENTIFIER]&nbsp;[_GenericParams_]<sup>?</sup>
> [_WhereClause_]<sup>?</sup> `=` [_Type_] `;`

A _type alias_ defines a new name for an existing [type]. Type aliases are
Expand Down Expand Up @@ -33,6 +33,6 @@ let _ = TypeAlias(5); // Doesn't work
```

[IDENTIFIER]: ../identifiers.md
[_Generics_]: generics.md
[_GenericParams_]: generics.md
[_WhereClause_]: generics.md#where-clauses
[_Type_]: ../types.md#type-expressions
4 changes: 2 additions & 2 deletions src/items/unions.md
Original file line number Diff line number Diff line change
Expand Up @@ -2,7 +2,7 @@

> **<sup>Syntax</sup>**\
> _Union_ :\
> &nbsp;&nbsp; `union` [IDENTIFIER]&nbsp;[_Generics_]<sup>?</sup> [_WhereClause_]<sup>?</sup>
> &nbsp;&nbsp; `union` [IDENTIFIER]&nbsp;[_GenericParams_]<sup>?</sup> [_WhereClause_]<sup>?</sup>
> `{`[_StructFields_] `}`

A union declaration uses the same syntax as a struct declaration, except with
Expand Down Expand Up @@ -177,7 +177,7 @@ generics, trait implementations, inherent implementations, coherence, pattern
checking, etc etc etc).

[IDENTIFIER]: ../identifiers.md
[_Generics_]: generics.md
[_GenericParams_]: generics.md
[_WhereClause_]: generics.md#where-clauses
[_StructFields_]: structs.md
[`transmute`]: ../../std/mem/fn.transmute.html
Expand Down
29 changes: 6 additions & 23 deletions src/paths.md
Original file line number Diff line number Diff line change
Expand Up @@ -50,37 +50,17 @@ mod m {
>
> _GenericArgs_ :\
> &nbsp;&nbsp; &nbsp;&nbsp; `<` `>`\
> &nbsp;&nbsp; | `<` _GenericArgsLifetimes_ `,`<sup>?</sup> `>`\
> &nbsp;&nbsp; | `<` _GenericArgsTypes_ `,`<sup>?</sup> `>`\
> &nbsp;&nbsp; | `<` _GenericArgsConsts_ `,`<sup>?</sup> `>`\
> &nbsp;&nbsp; | `<` _GenericArgsBindings_ `,`<sup>?</sup> `>`\
> &nbsp;&nbsp; | `<` _GenericArgsLifetimes_ `,` _GenericArgsTypes_ `,`<sup>?</sup> `>`\
> &nbsp;&nbsp; | `<` _GenericArgsLifetimes_ `,` _GenericArgsConsts_ `,`<sup>?</sup> `>`\
> &nbsp;&nbsp; | `<` _GenericArgsLifetimes_ `,` _GenericArgsBindings_ `,`<sup>?</sup> `>`\
> &nbsp;&nbsp; | `<` _GenericArgsLifetimes_ `,` _GenericArgsTypes_ `,` _GenericArgsConsts_ `,`<sup>?</sup> `>`\
> &nbsp;&nbsp; | `<` _GenericArgsLifetimes_ `,` _GenericArgsTypes_ `,` _GenericArgsBindings_ `,`<sup>?</sup> `>`\
> &nbsp;&nbsp; | `<` _GenericArgsLifetimes_ `,` _GenericArgsConsts_ `,` _GenericArgsBindings_ `,`<sup>?</sup> `>`\
> &nbsp;&nbsp; | `<` _GenericArgsTypes_ `,` _GenericArgsConsts_ `,` _GenericArgsBindings_ `,`<sup>?</sup> `>`\
> &nbsp;&nbsp; | `<` _GenericArgsLifetimes_ `,` _GenericArgsTypes_ `,` _GenericArgsConsts_ `,` _GenericArgsBindings_ `,`<sup>?</sup> `>`
> &nbsp;&nbsp; | `<` ( _GenericArg_ `,` )<sup>\*</sup> _GenericArg_ `,`<sup>?</sup> `>`
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>
> _GenericArgsLifetimes_ :\
> &nbsp;&nbsp; [_Lifetime_] (`,` [_Lifetime_])<sup>\*</sup>
>
> _GenericArgsTypes_ :\
> &nbsp;&nbsp; [_Type_] (`,` [_Type_])<sup>\*</sup>
>
> _GenericArgsConsts_ :\
> &nbsp;&nbsp; _GenericArgsConst_ (`,` _GenericArgsConst_)<sup>\*</sup>
> _GenericArg_ :\
> &nbsp;&nbsp; [_Lifetime_] | [_Type_] | _GenericArgsConst_ | _GenericArgsBinding_
>
> _GenericArgsConst_ :\
> &nbsp;&nbsp; &nbsp;&nbsp; [_BlockExpression_]\
> &nbsp;&nbsp; | [_LiteralExpression_]\
> &nbsp;&nbsp; | `-` [_LiteralExpression_]\
> &nbsp;&nbsp; | [_SimplePathSegment_]
>
> _GenericArgsBindings_ :\
> &nbsp;&nbsp; _GenericArgsBinding_ (`,` _GenericArgsBinding_)<sup>\*</sup>
>
> _GenericArgsBinding_ :\
> &nbsp;&nbsp; [IDENTIFIER] `=` [_Type_]

Expand All @@ -95,6 +75,9 @@ ambiguity with the less-than operator. This is colloquially known as "turbofish"
Vec::<u8>::with_capacity(1024);
```

The order of generic arguments is restricted to lifetime arguments, then type
arguments, then const arguments, then equality constraints.

Const arguments must be surrounded by braces unless they are a
[literal] or a single segment path.

Expand Down