public override IList <Token <TokenType> > Parse()
{
this.Current = new Token(this.Index);
char ch = GetNextChar();
while (ch != (char)0)
{
this.Status = this.Matrix.GetStatusTransform(this.Status, ch);
if (this.Status == ParserStatus.Error)
{
ExceptionHelper.ThrowParseError(this.Index - 1);
}
if (this.Status == ParserStatus.DPeekNext)
{
char next = PeekNextChar();
if (this.Matrix.GetCharType(next) == CharType.DQuot)
{
GetNextChar();//Note:skip the next double quot.
this.Current.Add(ch);
this.Status = ParserStatus.DQuot;
}
else
{
this.Current.Add(ch);
this.Status = ParserStatus.Start;//Note:accept the close quot and set to Start,so when scan next char,this token will be accepted.
}
}
else if (this.Status == ParserStatus.SPeekNext)
{
char next = PeekNextChar();
if (this.Matrix.GetCharType(next) == CharType.SQuot)
{
GetNextChar();//Note:skip the next single quot.
this.Current.Add(ch);
this.Status = ParserStatus.SQuot;
}
else
{
this.Current.Add(ch);
this.Status = ParserStatus.Start;//Note:accept the close quot and set to Start,so when scan next char,this token will be accepted.
}
}
else
{
if (!this.Matrix.TokenTerminated)
{
this.Current.Add(ch);
}
}
ch = GetNextChar();
}
AcceptLastToken(null, new LexicalParseEventArgs(ch, this.Status));//Note:Last token.
PostProcess();
return(this.Tokens);
}
//BNF:
//Value ::= Expr ? Expr : Expr | Expr
//Expr ::= Logic LogicOp(||,&&) Logic | Logic
//Logic ::= Compare CompareOp(>,>=,<,<=,==,!=) Compare | Compare
//Compare ::= Term (+-) Term | Term
//Term ::= Exponent (*/%) Exponent | Exponent
//Exponent ::= Unary (^) Unary
//Unary ::= Factor | -Factor | !Factor
//Factor ::= Obj.ID | Obj.ID(ValueList) | Obj[ValueList] | ID(ValueList) | Obj
//Obj ::= (Value) | ID | obj.ID,obj.ID(),obj[] | array[ValueList] | tuple[ID-Value pair] | regex[pattern] | new[ClassQualifier ValueList] | ClassQualifier
//ValueList ::= | Value | Value,ValueList
public override ExpressionLanguageAST Parse()
{
ExpressionLanguageAST ast = new ExpressionLanguageAST(Value());
if (this.Index < this.Tokens.Count)
{
ExceptionHelper.ThrowParseError(this.Tokens[this.Index].Position);
}
Trace(ast);
return(ast);
}
private Node Obj()
{
Token <TokenType> t = PeekNextToken();
switch (t.TokenType)
{
case TokenType.Array:
return(Array());
case TokenType.Hash:
return(Hash());
case TokenType.Regex:
return(Regex());
case TokenType.New:
return(New());
case TokenType.Left_Parenthesis:
GetNextToken();
Node node = Value();
Token <TokenType> rightToken = GetNextToken();
if (rightToken.TokenType != TokenType.Right_Parenthesis)
{
ExceptionHelper.ThrowExpectToken(TokenType.Right_Parenthesis, t.Position);
}
return(node);
case TokenType.ID:
Token <TokenType> idToken = GetNextToken();
Token <TokenType> next = PeekNextToken();
if (next.TokenType == TokenType.ClassQualifier)
{
List <string> strList = new List <string>();
strList.Add(idToken.TokenValue);
while (next.TokenType == TokenType.ClassQualifier)
{
GetNextToken(); //Note:Get the :: operator
idToken = GetNextToken();
if (idToken.TokenType != TokenType.ID)
{
ExceptionHelper.ThrowExpectToken(TokenType.ID, idToken.Position);
}
strList.Add(idToken.TokenValue);
next = PeekNextToken();
}
return(new ClassQualifierNode(strList));
}
else
{
return(new SimpleNode(idToken));
}
case TokenType.String:
case TokenType.Long:
case TokenType.Decimal:
case TokenType.Boolean:
Token <TokenType> valToken = GetNextToken();
return(new SimpleNode(valToken));
default:
ExceptionHelper.ThrowParseError(t.Position);
return(null);
}
}