编译原理虎书java版本–Chapter 2-3
文件:
options {
JAVA_UNICODE_ESCAPE = true;
}
PARSER_BEGIN(MiniJavaParser)
public class MiniJavaParser {}
PARSER_END(MiniJavaParser)
// Insert a specification of a lexical analysis here.
TOKEN :
{
< LPAREN: "(" >
| < RPAREN: ")" >
| < LSQPAREN: "[" >
| < RSQPAREN: "]" >
| < LBRACE: "{" >
| < RBRACE: "}" >
| < DOT: "." >
| < ASSIGN: "=" >
| < LT: "<" >
| < PLUS: "+" >
| < MINUS: "-" >
| < AND : "&&" >
| < NOT : "!" >
| < SEMICOLON: ";" >
| < PUBLIC: "public" >
| < RETURN: "return" >
| < BOOLEAN: "boolean" >
| < CLASS: "class" >
| < INTERFACE: "interface" >
| < ELSE: "else" >
| < EXTENDS: "extends" >
| < FALSE: "false" >
| < IF: "if" >
| < WHILE: "while" >
| < INTEGER: "int" >
| < LENGTH: "length" >
| < MAIN: "main" >
| < NEW: "new" >
| < STATIC: "static" >
| < STRING: "String" >
| < THIS: "this" >
| < TRUE: "true" >
| < PRINT: "System.out.println" >
| < VOID: "void" >
}
TOKEN : /* LITERALS */
{
< INTEGER_LITERAL: ( ["1"-"9"] (["0"-"9"])* | "0" ) >
}
TOKEN : /* IDENTIFIERS */
{
< IDENTIFIER: (|)* >
|
< #LETTER:
[
"u0024",
"u0041"-"u005a",
"u005f",
"u0061"-"u007a",
"u00c0"-"u00d6",
"u00d8"-"u00f6",
"u00f8"-"u00ff",
"u0100"-"u1fff",
"u3040"-"u318f",
"u3300"-"u337f",
"u3400"-"u3d2d",
"u4e00"-"u9fff",
"uf900"-"ufaff"
]
|
< #DIGIT:
[
"u0030"-"u0039",
"u0660"-"u0669",
"u06f0"-"u06f9",
"u0966"-"u096f",
"u09e6"-"u09ef",
"u0a66"-"u0a6f",
"u0ae6"-"u0aef",
"u0b66"-"u0b6f",
"u0be7"-"u0bef",
"u0c66"-"u0c6f",
"u0ce6"-"u0cef",
"u0d66"-"u0d6f",
"u0e50"-"u0e59",
"u0ed0"-"u0ed9",
"u1040"-"u1049"
]
}
SKIP :
{
< " " >
| < "t" >
| < "n" >
| < "r" >
| < "//" (~["n"])* "n" >
| <"/*" (~["*"])* "*" (~["/"] (~["*"])* "*")* "/">
}
// The following is a simple grammar that will allow you
// to test the generated lexer.
void Program() :
{}
{
MainClass() (ClassDecl())*
}
void MainClass() :
{}
{
"class" "{" "public" "static" "void" "main" "(" "String" "[" "]" "{" Statement() "}" "}"
}
void ext() :
{}
{
("extends" )?
}
void ClassDecl() :
{}
{
"class" ext() "{" (VarDecl())* (MethodDecl())* "}"
}
void VarDecl():
{}
{ Type() ";"}
void MethodDecl():
{}
{"public" Type()
"(" FormaList() ")"
"{" ( LOOKAHEAD(2) VarDecl() )* (Statement())* "return" Exp() ";" "}"
}
void FormaList():
{}
{(Type() "FormalRest()")?}
void FormaRest():
{}
{"," Type() }
void Type():
{}
{
|"boolean"
|LOOKAHEAD(2)
"int"
|"int" "[" "]"
}
void Statement():
{}
{"{" (Statement())* "}"
|"while" "(" Exp() ")" Statement()
|"System.out.println" "(" Exp() ")"
| instat1() "=" Exp() ";"
|"if" "(" Exp() ")" Statement() inif()
}
void inif():
{}
{(LOOKAHEAD(2) "else" Statement())?}
void instat1():
{}
{("[" Exp() "]")?}
void Exp():
{}
{Expa() (LOOKAHEAD(2) (Expb()))?
}
void Expa():
{}
{"true"
|"false"
|
|"this"
|"!" Exp()
|"(" Exp() ")"
|LOOKAHEAD(2)
"new" "int" "[" Exp() "]"
|"new" "(" ")"
}
void Expb():
{}
{
op() Exp()
|"[" Exp() "]"Exp()
|LOOKAHEAD(2)
"." "length"
|"."
}
void op():
{}
{"&&"
|"<"
|"+"
|"-"
|"*"}
void ExpList():
{}
{(Exp() (ExpRest())*)?}
void ExpRest():
{}
{"," Exp()}
void Goal() :
{}
{
( MiniJavaToken() )*
}
void MiniJavaToken():
{}
{
"class" | | "{" | "public" | "static" | "void" |
"main" | "(" | "String" | "[" | "]" | ")" | "}" | "extends" | ";"
| "return" | "," | "int" | "boolean" | "=" | "if" | "else" | "while"
| "System.out.println" | "&&" | "<" | "+" | "-" | "*" | "." |
"length" | | "true" | "false" | "this" | "new" |
"!"
}