プログラミング言語の構文の複雑さについて考える 〜Java vs. Scala〜 ref: http://qiita.com/kmizu/items/62db9d44f929055fbfc7

file0.txt

‘try’ (‘{’ Block ‘}’ | Expr) [‘catch’ ‘{’ CaseClauses ‘}’] [‘finally’ Expr]

file1.txt

TryStatement:
    try Block Catches 
  | try Block [Catches] Finally 
  | TryWithResourcesStatement;
Catches:
  CatchClause {CatchClause};
CatchClause:
  catch ( CatchFormalParameter ) Block;
CatchFormalParameter:
  {VariableModifier} CatchType VariableDeclaratorId;
CatchType:
  UnannClassType {| ClassType};
Finally:
  finally Block;

file2.txt

  ClassDef          ::=  id [TypeParamClause] {ConstrAnnotation} 
                         [AccessModifier]
                         ClassParamClauses ClassTemplateOpt
  TraitDef          ::=  id [TypeParamClause] TraitTemplateOpt
  ObjectDef         ::=  id ClassTemplateOpt
  ClassTemplateOpt  ::=  ‘extends’ ClassTemplate | [[‘extends’] TemplateBody]
  TraitTemplateOpt  ::=  ‘extends’ TraitTemplate | [[‘extends’] TemplateBody]
  ClassTemplate     ::=  [EarlyDefs] ClassParents [TemplateBody]
  TraitTemplate     ::=  [EarlyDefs] TraitParents [TemplateBody]

file3.txt

TypeDeclaration:
    ClassDeclaration 
  | InterfaceDeclaration;

ClassDeclaration:
    NormalClassDeclaration 
  | EnumDeclaration;

NormalClassDeclaration:
  {ClassModifier} class Identifier [TypeParameters] [Superclass] 
    [Superinterfaces] ClassBody;

EnumDeclaration:
  {ClassModifier} enum Identifier [Superinterfaces] EnumBody;

InterfaceDeclaration:
    AnnotationTypeDeclaration
  | NormalInterfaceDeclaration;

NormalInterfaceDeclaration:
  {InterfaceModifier} interface Identifier [TypeParameters] 
    [ExtendsInterfaces] InterfaceBody;

InterfaceBody: { {InterfaceMemberDeclaration} };
InterfaceMemberDeclaration:
    ConstantDeclaration 
  | InterfaceMethodDeclaration 
  | ClassDeclaration 
  | InterfaceDeclaration;

ClassBody: { {ClassBodyDeclaration} };
ClassBodyDeclaration:
    ClassMemberDeclaration 
  | InstanceInitializer 
  | StaticInitializer 
  | ConstructorDeclaration;