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Port context-free syntax.
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‎docs/_spec/13-syntax-summary.md‎

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@@ -89,242 +89,87 @@ semi ::= ‘;’ | nl {nl}
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## Context-free Syntax
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´\color{red}{\text{TODO SCALA3: Once we're done porting the spec, make sure that
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the references to grammar productions in the rest of the spec match this.}}´
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The context-free syntax of Scala is given by the following EBNF grammar:
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```ebnf
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Literal ::= [‘-’] integerLiteral
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| [‘-’] floatingPointLiteral
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| booleanLiteral
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| characterLiteral
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| stringLiteral
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| interpolatedString
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| symbolLiteral
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| ‘null’
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QualId ::= id {‘.’ id}
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ids ::= id {‘,’ id}
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Path ::= StableId
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| [id ‘.’] ‘this’
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StableId ::= id
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| Path ‘.’ id
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| [id ‘.’] ‘super’ [ClassQualifier] ‘.’ id
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ClassQualifier ::= ‘[’ id ‘]’
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Type ::= FunctionArgTypes ‘=>’ Type
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| InfixType [ExistentialClause]
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FunctionArgTypes ::= InfixType
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| ‘(’ [ ParamType {‘,’ ParamType } ] ‘)’
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ExistentialClause ::= ‘forSome’ ‘{’ ExistentialDcl {semi ExistentialDcl} ‘}’
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ExistentialDcl ::= ‘type’ TypeDcl
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| ‘val’ ValDcl
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InfixType ::= CompoundType {id [nl] CompoundType}
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CompoundType ::= AnnotType {‘with’ AnnotType} [Refinement]
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| Refinement
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AnnotType ::= SimpleType {Annotation}
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SimpleType ::= SimpleType TypeArgs
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| SimpleType ‘#’ id
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| StableId
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| Path ‘.’ ‘type’
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| ‘(’ Types ‘)’
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TypeArgs ::= ‘[’ Types ‘]’
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Types ::= Type {‘,’ Type}
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Refinement ::= [nl] ‘{’ RefineStat {semi RefineStat} ‘}’
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RefineStat ::= Dcl
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| ‘type’ TypeDef
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|
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TypePat ::= Type
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Ascription ::= ‘:’ InfixType
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| ‘:’ Annotation {Annotation}
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| ‘:’ ‘_’ ‘*’
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Expr ::= (Bindings | [‘implicit’] id | ‘_’) ‘=>’ Expr
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| Expr1
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Expr1 ::= ‘if’ ‘(’ Expr ‘)’ {nl} Expr [[semi] ‘else’ Expr]
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| ‘while’ ‘(’ Expr ‘)’ {nl} Expr
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| ‘try’ Expr [‘catch’ Expr] [‘finally’ Expr]
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| ‘do’ Expr [semi] ‘while’ ‘(’ Expr ‘)’
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| ‘for’ (‘(’ Enumerators ‘)’ | ‘{’ Enumerators ‘}’) {nl} [‘yield’] Expr
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| ‘throw’ Expr
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| ‘return’ [Expr]
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| [SimpleExpr ‘.’] id ‘=’ Expr
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| PrefixOperator SimpleExpr ‘=’ Expr
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| SimpleExpr1 ArgumentExprs ‘=’ Expr
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| PostfixExpr
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| PostfixExpr Ascription
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| PostfixExpr ‘match’ ‘{’ CaseClauses ‘}’
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PostfixExpr ::= InfixExpr [id [nl]]
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InfixExpr ::= PrefixExpr
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| InfixExpr id [nl] InfixExpr
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PrefixExpr ::= [PrefixOperator] SimpleExpr
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PrefixOperator ::= ‘-’ | ‘+’ | ‘~’ | ‘!’
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SimpleExpr ::= ‘new’ (ClassTemplate | TemplateBody)
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| BlockExpr
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| SimpleExpr1 [‘_’]
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SimpleExpr1 ::= Literal
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| Path
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| ‘_’
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| ‘(’ [Exprs] ‘)’
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| SimpleExpr ‘.’ id
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| SimpleExpr TypeArgs
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| SimpleExpr1 ArgumentExprs
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| XmlExpr
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Exprs ::= Expr {‘,’ Expr}
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ArgumentExprs ::= ‘(’ [Exprs] ‘)’
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| ‘(’ [Exprs ‘,’] PostfixExpr ‘:’ ‘_’ ‘*’ ‘)’
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| [nl] BlockExpr
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BlockExpr ::= ‘{’ CaseClauses ‘}’
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| ‘{’ Block ‘}’
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Block ::= BlockStat {semi BlockStat} [ResultExpr]
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BlockStat ::= Import
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| {Annotation} [‘implicit’] [‘lazy’] Def
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| {Annotation} {LocalModifier} TmplDef
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| Expr1
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|
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ResultExpr ::= Expr1
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| (Bindings | ([‘implicit’] id | ‘_’) ‘:’ CompoundType) ‘=>’ Block
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Enumerators ::= Generator {semi Generator}
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Generator ::= [‘case’] Pattern1 ‘<-’ Expr {[semi] Guard | semi Pattern1 ‘=’ Expr}
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CaseClauses ::= CaseClause { CaseClause }
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CaseClause ::= ‘case’ Pattern [Guard] ‘=>’ Block
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Guard ::= ‘if’ PostfixExpr
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Pattern ::= Pattern1 { ‘|’ Pattern1 }
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Pattern1 ::= boundvarid ‘:’ TypePat
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| ‘_’ ‘:’ TypePat
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| Pattern2
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Pattern2 ::= id [‘@’ Pattern3]
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| Pattern3
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Pattern3 ::= SimplePattern
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| SimplePattern { id [nl] SimplePattern }
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SimplePattern ::= ‘_’
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| varid
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| Literal
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| StableId
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| StableId ‘(’ [Patterns] ‘)’
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| StableId ‘(’ [Patterns ‘,’] [id ‘@’] ‘_’ ‘*’ ‘)’
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| ‘(’ [Patterns] ‘)’
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| XmlPattern
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Patterns ::= Pattern [‘,’ Patterns]
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| ‘_’ ‘*’
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TypeParamClause ::= ‘[’ VariantTypeParam {‘,’ VariantTypeParam} ‘]’
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FunTypeParamClause::= ‘[’ TypeParam {‘,’ TypeParam} ‘]’
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VariantTypeParam ::= {Annotation} [‘+’ | ‘-’] TypeParam
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TypeParam ::= (id | ‘_’) [TypeParamClause] [‘>:’ Type] [‘<:’ Type]
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{‘<%’ Type} {‘:’ Type}
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ParamClauses ::= {ParamClause} [[nl] ‘(’ ‘implicit’ Params ‘)’]
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ParamClause ::= [nl] ‘(’ [Params] ‘)’
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Params ::= Param {‘,’ Param}
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Param ::= {Annotation} id [‘:’ ParamType] [‘=’ Expr]
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ParamType ::= Type
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| ‘=>’ Type
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| Type ‘*’
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ClassParamClauses ::= {ClassParamClause}
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[[nl] ‘(’ ‘implicit’ ClassParams ‘)’]
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ClassParamClause ::= [nl] ‘(’ [ClassParams] ‘)’
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ClassParams ::= ClassParam {‘,’ ClassParam}
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ClassParam ::= {Annotation} {Modifier} [(‘val’ | ‘var’)]
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id ‘:’ ParamType [‘=’ Expr]
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Bindings ::= ‘(’ Binding {‘,’ Binding} ‘)’
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Binding ::= (id | ‘_’) [‘:’ Type]
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Modifier ::= LocalModifier
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| AccessModifier
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| ‘override’
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LocalModifier ::= ‘abstract’
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| ‘final’
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| ‘sealed’
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| ‘implicit’
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| ‘lazy’
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AccessModifier ::= (‘private’ | ‘protected’) [AccessQualifier]
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AccessQualifier ::= ‘[’ (id | ‘this’) ‘]’
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Annotation ::= ‘@’ SimpleType {ArgumentExprs}
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ConstrAnnotation ::= ‘@’ SimpleType ArgumentExprs
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TemplateBody ::= [nl] ‘{’ [SelfType] TemplateStat {semi TemplateStat} ‘}’
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TemplateStat ::= Import
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| {Annotation [nl]} {Modifier} Def
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| {Annotation [nl]} {Modifier} Dcl
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| Expr
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|
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SelfType ::= id [‘:’ Type] ‘=>’
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| ‘this’ ‘:’ Type ‘=>’
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Import ::= ‘import’ ImportExpr {‘,’ ImportExpr}
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ImportExpr ::= StableId ‘.’ (id | ‘_’ | ImportSelectors)
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ImportSelectors ::= ‘{’ {ImportSelector ‘,’} (ImportSelector | ‘_’) ‘}’
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ImportSelector ::= id [‘=>’ id | ‘=>’ ‘_’]
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Dcl ::= ‘val’ ValDcl
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| ‘var’ VarDcl
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| ‘def’ FunDcl
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| ‘type’ {nl} TypeDcl
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ValDcl ::= ids ‘:’ Type
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VarDcl ::= ids ‘:’ Type
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FunDcl ::= FunSig [‘:’ Type]
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FunSig ::= id [FunTypeParamClause] ParamClauses
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TypeDcl ::= id [TypeParamClause] [‘>:’ Type] [‘<:’ Type]
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PatVarDef ::= ‘val’ PatDef
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| ‘var’ VarDef
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Def ::= PatVarDef
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| ‘def’ FunDef
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| ‘type’ {nl} TypeDef
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| TmplDef
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PatDef ::= Pattern2 {‘,’ Pattern2} [‘:’ Type] ‘=’ Expr
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VarDef ::= PatDef
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| ids ‘:’ Type ‘=’ ‘_’
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FunDef ::= FunSig [‘:’ Type] ‘=’ Expr
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| FunSig [nl] ‘{’ Block ‘}’
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| ‘this’ ParamClause ParamClauses
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(‘=’ ConstrExpr | [nl] ConstrBlock)
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TypeDef ::= id [TypeParamClause] ‘=’ Type
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TmplDef ::= [‘case’] ‘class’ ClassDef
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| [‘case’] ‘object’ ObjectDef
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| ‘trait’ TraitDef
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ClassDef ::= id [TypeParamClause] {ConstrAnnotation} [AccessModifier]
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ClassParamClauses ClassTemplateOpt
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TraitDef ::= id [TypeParamClause] TraitTemplateOpt
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ObjectDef ::= id ClassTemplateOpt
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ClassTemplateOpt ::= ‘extends’ ClassTemplate | [[‘extends’] TemplateBody]
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TraitTemplateOpt ::= ‘extends’ TraitTemplate | [[‘extends’] TemplateBody]
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ClassTemplate ::= [EarlyDefs] ClassParents [TemplateBody]
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TraitTemplate ::= [EarlyDefs] TraitParents [TemplateBody]
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ClassParents ::= Constr {‘with’ AnnotType}
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TraitParents ::= AnnotType {‘with’ AnnotType}
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Constr ::= AnnotType {ArgumentExprs}
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EarlyDefs ::= ‘{’ [EarlyDef {semi EarlyDef}] ‘}’ ‘with’
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EarlyDef ::= {Annotation [nl]} {Modifier} PatVarDef
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ConstrExpr ::= SelfInvocation
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| ConstrBlock
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ConstrBlock ::= ‘{’ SelfInvocation {semi BlockStat} ‘}’
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SelfInvocation ::= ‘this’ ArgumentExprs {ArgumentExprs}
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TopStatSeq ::= TopStat {semi TopStat}
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TopStat ::= {Annotation [nl]} {Modifier} TmplDef
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| Import
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| Packaging
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| PackageObject
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|
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Packaging ::= ‘package’ QualId [nl] ‘{’ TopStatSeq ‘}’
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PackageObject ::= ‘package’ ‘object’ ObjectDef
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CompilationUnit ::= {‘package’ QualId semi} TopStatSeq
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RefineDcl ::= ‘val’ ValDcl
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| ‘def’ DefDcl
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| ‘type’ {nl} TypeDcl
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Dcl ::= RefineDcl
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| ‘var’ VarDcl
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ValDcl ::= ids ‘:’ Type
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VarDcl ::= ids ‘:’ Type
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DefDcl ::= DefSig ‘:’ Type
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DefSig ::= id [DefTypeParamClause] [TypelessClauses] [DefImplicitClause]
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TypeDcl ::= id [TypeParamClause] {FunParamClause} TypeBounds
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Def ::= ‘val’ PatDef
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| ‘var’ PatDef
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| ‘def’ DefDef
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| ‘type’ {nl} TypeDcl
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| TmplDef
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PatDef ::= ids [‘:’ Type] ‘=’ Expr
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| Pattern2 [‘:’ Type] ‘=’ Expr
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DefDef ::= DefSig [‘:’ Type] ‘=’ Expr
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| ‘this’ TypelessClauses [DefImplicitClause] ‘=’ ConstrExpr
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TmplDef ::= ([‘case’] ‘class’ | ‘trait’) ClassDef
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| [‘case’] ‘object’ ObjectDef
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| ‘enum’ EnumDef
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| ‘given’ GivenDef
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ClassDef ::= id ClassConstr [Template]
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ClassConstr ::= [ClsTypeParamClause] [ConstrMods] ClsParamClauses
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ConstrMods ::= {Annotation} [AccessModifier]
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ObjectDef ::= id [Template]
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EnumDef ::= id ClassConstr InheritClauses EnumBody
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GivenDef ::= [GivenSig] (AnnotType [‘=’ Expr] | StructuralInstance)
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GivenSig ::= [id] [DefTypeParamClause] {UsingParamClause} ‘:’ -- one of `id`, `DefTypeParamClause`, `UsingParamClause` must be present
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StructuralInstance ::= ConstrApp {‘with’ ConstrApp} [‘with’ WithTemplateBody]
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Extension ::= ‘extension’ [DefTypeParamClause] {UsingParamClause}
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‘(’ DefTermParam ‘)’ {UsingParamClause} ExtMethods
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ExtMethods ::= ExtMethod | [nl] <<< ExtMethod {semi ExtMethod} >>>
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ExtMethod ::= {Annotation [nl]} {Modifier} ‘def’ DefDef
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| Export
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Template ::= InheritClauses [TemplateBody]
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InheritClauses ::= [‘extends’ ConstrApps] [‘derives’ QualId {‘,’ QualId}]
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ConstrApps ::= ConstrApp ({‘,’ ConstrApp} | {‘with’ ConstrApp})
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ConstrApp ::= SimpleType1 {Annotation} {ParArgumentExprs}
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ConstrExpr ::= SelfInvocation
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| <<< SelfInvocation {semi BlockStat} >>>
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SelfInvocation ::= ‘this’ ArgumentExprs {ArgumentExprs}
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WithTemplateBody ::= <<< [SelfType] TemplateStat {semi TemplateStat} >>>
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TemplateBody ::= :<<< [SelfType] TemplateStat {semi TemplateStat} >>>
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TemplateStat ::= Import
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| Export
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| {Annotation [nl]} {Modifier} Def
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| {Annotation [nl]} {Modifier} Dcl
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| Extension
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| Expr1
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| EndMarker
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|
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SelfType ::= id [‘:’ InfixType] ‘=>’
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| ‘this’ ‘:’ InfixType ‘=>’
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EnumBody ::= :<<< [SelfType] EnumStat {semi EnumStat} >>>
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EnumStat ::= TemplateStat
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| {Annotation [nl]} {Modifier} EnumCase
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EnumCase ::= ‘case’ (id ClassConstr [‘extends’ ConstrApps]] | ids)
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TopStats ::= TopStat {semi TopStat}
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TopStat ::= Import
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| Export
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| {Annotation [nl]} {Modifier} Def
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| Extension
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| Packaging
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| PackageObject
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| EndMarker
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|
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Packaging ::= ‘package’ QualId :<<< TopStats >>>
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PackageObject ::= ‘package’ ‘object’ ObjectDef
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CompilationUnit ::= {‘package’ QualId semi} TopStats
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```
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<!-- TODO add:
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SeqPattern ::= ...
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SimplePattern ::= StableId [TypePatArgs] [‘(’ [SeqPatterns] ‘)’]
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TypePatArgs ::= ‘[’ TypePatArg {‘,’ TypePatArg} ‘]’
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TypePatArg ::= ‘_’ | varid}
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-->

‎docs/_spec/TODOreference/syntax.md‎ renamed to ‎docs/_spec/APPLIEDreference/syntax.md‎

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@@ -18,8 +18,6 @@ productions map to AST nodes.
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-->
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<!-- Everything but "Context-free Syntax" already merged into _spec. -->
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<!--
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The following description of Scala tokens uses literal characters `‘c’` when
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referring to the ASCII fragment `\u0000` – `\u007F`.
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See the [separate section on soft keywords](./soft-modifier.md) for additional
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details on where a soft keyword is recognized.
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-->
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## Context-free Syntax
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The context-free syntax of Scala is given by the following EBNF

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