二、Mini Java的文法
BNF
| Goal | ::= | MainClass ( TypeDeclaration )* <EOF> |
| MainClass | ::= | “class” Identifier “{” “public” “static” “void” “main” “(” “String” “[” “]” Identifier “)” “{” PrintStatement “}” “}” |
| TypeDeclaration | ::= | ClassDeclaration |
| | | ClassExtendsDeclaration | |
| ClassDeclaration | ::= | “class” Identifier “{” ( VarDeclaration )* ( MethodDeclaration )* “}” |
| ClassExtendsDeclaration | ::= | “class” Identifier “extends” Identifier “{” ( VarDeclaration )* ( MethodDeclaration )* “}” |
| VarDeclaration | ::= | Type Identifier “;” |
| MethodDeclaration | ::= | “public” Type Identifier “(” ( FormalParameterList )? “)” “{” ( VarDeclaration )* ( Statement )* “return” Expression “;” “}” |
| FormalParameterList | ::= | FormalParameter ( FormalParameterRest )* |
| FormalParameter | ::= | Type Identifier |
| FormalParameterRest | ::= | “,” FormalParameter |
| Type | ::= | ArrayType |
| | | BooleanType | |
| | | IntegerType | |
| | | Identifier | |
| ArrayType | ::= | “int” “[” “]” |
| BooleanType | ::= | “boolean” |
| IntegerType | ::= | “int” |
| Statement | ::= | Block |
| | | AssignmentStatement | |
| | | ArrayAssignmentStatement | |
| | | IfStatement | |
| | | WhileStatement | |
| | | PrintStatement | |
| Block | ::= | “{” ( Statement )* “}” |
| AssignmentStatement | ::= | Identifier “=” Expression “;” |
| ArrayAssignmentStatement | ::= | Identifier “[” Expression “]” “=” Expression “;” |
| IfStatement | ::= | “if” “(” Expression “)” Statement “else” Statement |
| WhileStatement | ::= | “while” “(” Expression “)” Statement |
| PrintStatement | ::= | “System.out.println” “(” Expression “)” “;” |
| Expression | ::= | AndExpression |
| | | CompareExpression | |
| | | PlusExpression | |
| | | MinusExpression | |
| | | TimesExpression | |
| | | ArrayLookup | |
| | | ArrayLength | |
| | | MessageSend | |
| | | PrimaryExpression | |
| AndExpression | ::= | PrimaryExpression “&&” PrimaryExpression |
| CompareExpression | ::= | PrimaryExpression “<” PrimaryExpression |
| PlusExpression | ::= | PrimaryExpression “+” PrimaryExpression |
| MinusExpression | ::= | PrimaryExpression “-” PrimaryExpression |
| TimesExpression | ::= | PrimaryExpression “*” PrimaryExpression |
| ArrayLookup | ::= | PrimaryExpression “[” PrimaryExpression “]” |
| ArrayLength | ::= | PrimaryExpression “.” “length” |
| MessageSend | ::= | PrimaryExpression “.” Identifier “(” ( ExpressionList )? “)” |
| ExpressionList | ::= | Expression ( ExpressionRest )* |
| ExpressionRest | ::= | “,” Expression |
| PrimaryExpression | ::= | IntegerLiteral |
| | | TrueLiteral | |
| | | FalseLiteral | |
| | | Identifier | |
| | | ThisExpression | |
| | | ArrayAllocationExpression | |
| | | AllocationExpression | |
| | | NotExpression | |
| | | BracketExpression | |
| IntegerLiteral | ::= | <INTEGER_LITERAL> |
| TrueLiteral | ::= | “true” |
| FalseLiteral | ::= | “false” |
| Identifier | ::= | <IDENTIFIER> |
| ThisExpression | ::= | “this” |
| ArrayAllocationExpression | ::= | “new” “int” “[” Expression “]” |
| AllocationExpression | ::= | “new” Identifier “(” “)” |
| NotExpression | ::= | “!” Expression |
| BracketExpression | ::= | “(” Expression “)” |
-- EOF --
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本文链接地址：Mini Java编译器（二）
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