// Arguments = "(" [Expression { COMMA Expression }] ")"
private List <Expression> Arguments()
{
int pos = S.Pos;
List <Expression> args = new List <Expression>();
if (S.Token == LPAREN)
{
S.NextToken();
if (S.Token != RPAREN)
{
args.Add(GetExpression());
while (S.Token == COMMA)
{
S.NextToken();
args.Add(GetExpression());
}
}
Accept(RPAREN);
}
else
{
throw ScriptCompileException.CreateSyntaxError(S.Line, S.Col, S.Token, S.TokenString);
}
return(args);
}
private string Ident()
{
if (S.Token == IDENTIFIER)
{
string name = S.TokenString;
S.NextToken();
return(name);
}
else
{
throw ScriptCompileException.CreateIsNotIdentifier(S.TokenString);
}
}
public void AddSymbolVar(string localName)
{
Dictionary <string, Int32> symbolTable = _blockSymbolTable[_blockSymbolTable.Count - 1];
int at;
if (symbolTable.TryGetValue(localName, out at) == false) //不存在
{
symbolTable.Add(localName, IndexTop++);
}
else
{
throw ScriptCompileException.CreateContentExist(localName);
}
}
public void Accept(int token)
{
if (token == SEMI) // ; 处理,可以不加;
{
if (S.Token == token)
{
S.NextToken();
}
return;
}
if (S.Token == token)
{
S.NextToken();
}
else
{
throw ScriptCompileException.CreateSyntaxError(S.Line, S.Col, S.Token, S.TokenString);
}
}
private bool FormalParameter()
{
if (S.Token == IDENTIFIER) //标识符
{
Instructor.CompileIndexStack.AddSymbolVar(S.TokenString);
S.NextToken();
return(false);
}
else if (S.Token == UntPar)
{
Instructor.CompileIndexStack.AddSymbolVar("args");
S.NextToken();
return(true);
}
else
{
throw ScriptCompileException.CreateSyntaxError(S.Line, S.Col, S.Token, S.TokenString);
}
}
private Expression Term3()
{
Expression t = null;
switch (S.Token)
{
case PLUSPLUS: // 例如 ++i
S.NextToken();
t = Term3();
t = E.At(S.Pos).PosInc(t, true);
break;
case SUBSUB: // 例如 --i
S.NextToken();
t = Term3();
t = E.At(S.Pos).PosDec(t, true);
break;
case THIS:
S.NextToken();
if (S.Token == EQ)
{
throw ScriptCompileException.CreateSyntaxError(S.Line, S.Col, S.Token, S.TokenString);
}
t = E.At(S.Pos).GetThisValue();
break;
case FALSE:
Contract.Assert(S.TokenString == "false");
t = E.At(S.Pos).Flase();
S.NextToken();
break;
case TRUE:
Contract.Assert(S.TokenString == "true");
t = E.At(S.Pos).True();
S.NextToken();
break;
case NUMBER: //数字
t = E.At(S.Pos).Number(S.TokenString);
S.NextToken();
break;
case STRINGLITERAL: //字符串
t = E.At(S.Pos).String(S.TokenString);
S.NextToken();
break;
case FUNCTION: //函数
S.NextToken();
t = MethodDeclaratorRest();
break;
case LBRACE:
t = TableInitializer(t);
break;
case IDENTIFIER:
string ident = Ident();
if (S.Token == EQ)
{
mode = LValue;
S.NextToken();
if (S.Token != Nil)
{
t = E.At(S.Pos).Select(t, ident, true);
}
else
{
t = E.At(S.Pos).Remove(t, ident);
mode = EXPR;
}
}
else
{
t = E.At(S.Pos).Select(t, ident, false);
if (S.Token == LPAREN)
{
t = Arguments(t);
}
}
break;
default:
throw ScriptCompileException.CreateSyntaxError(S.Line, S.Col, S.Token, S.TokenString);
}
while (true)
{
if (S.Token == DOT)
{
S.NextToken();
string ident = Ident();
if (S.Token == EQ)
{
mode = LValue;
S.NextToken();
if (S.Token != Nil)
{
t = E.At(S.Pos).Select(t, ident, true);
}
else
{
t = E.At(S.Pos).Remove(t, ident);
mode = EXPR;
}
}
else if (S.Token == LPAREN)
{
Expression own = t;
t = E.At(S.Pos).Select(t, ident, false);
t = Arguments(own, t);
}
else
{
t = E.At(S.Pos).Select(t, ident, false);
}
}
else if (S.Token == LPAREN) // (
{
t = Arguments(t);
}
else if (S.Token == LBRACKET) // [
{
S.NextToken();
Expression t1 = Term();
Accept(RBRACKET);
if (S.Token == EQ)
{
mode = LValue;
S.NextToken();
if (S.Token != Nil)
{
t = E.At(S.Pos).Select(t, t1, true);
}
else
{
t = E.At(S.Pos).Remove(t, t1);
mode = EXPR;
}
}
else if (S.Token == LPAREN)
{
Expression own = t;
t = E.At(S.Pos).Select(t, t1, false);
t = Arguments(own, t);
}
else
{
t = E.At(S.Pos).Select(t, t1, false);
}
}
else
{
break;
}
}
while ((S.Token == PLUSPLUS || S.Token == SUBSUB) && (mode & EXPR) != 0)
{
mode = EXPR;
// t = E.At(S.Pos).Unary(S.Token == PLUSPLUS ? Tree.POSTINC : Tree.POSTDEC, t);
if (S.Token == PLUSPLUS) // 后加 例如 i++;
{
t = E.At(S.Pos).PosInc(t, false);
}
else
{
t = E.At(S.Pos).PosDec(t, false);
}
S.NextToken();
}
return(t);
}
private Expression Statement()
{
switch (S.Token)
{
case LBRACE:
return(Block());
case IF:
{
S.NextToken();
Expression cond = ParExpression();
Expression thenpart = Statement();
Expression elsepart = null;
if (S.Token == ELSE)
{
S.NextToken();
elsepart = Statement();
}
return(E.At(S.Pos).IfThenElse(cond, thenpart, elsepart));
}
case FOR:
{
S.NextToken();
Accept(LPAREN);
Expression inits = S.Token == SEMI?Expression.Empty() : GetExpression();
Accept(SEMI);
Expression cond = S.Token == SEMI?Expression.Empty() : GetExpression();
Accept(SEMI);
Expression steps = S.Token == RPAREN?Expression.Empty() : GetExpression();
Accept(RPAREN);
loopLabelStack.Push(Expression.Label());
Expression body = Statement();
return(E.At(S.Pos).ForLoop(inits, cond, steps, body, loopLabelStack.Pop()));
}
case WHILE:
{
S.NextToken();
Expression cond = ParExpression();
loopLabelStack.Push(Expression.Label());
Expression body = Statement();
Expression t = E.At(S.Pos).WhileLoop(cond, body, loopLabelStack.Pop());
return(t);
}
case DO:
{
S.NextToken();
loopLabelStack.Push(Expression.Label());
Expression body = Statement();
Accept(WHILE);
Expression cond = ParExpression();
Expression t = E.At(S.Pos).DoWhileLoop(body, cond, loopLabelStack.Pop());
return(t);
}
case BREAK:
{
S.NextToken();
//应该先判断是否Peek()为空,以后在处理
Expression t = E.At(S.Pos).Break(loopLabelStack.Peek());
Accept(SEMI);
return(t);
}
case RETURN:
{
S.NextToken();
Expression result = S.Token == SEMI ? null : VariableInitializer();
//应该先判断是否Peek()为空,以后在处理
Expression t = E.At(S.Pos).Return(funcReturnStack.Peek(), result);
Accept(SEMI);
return(t);
}
case ELSE:
{
throw ScriptCompileException.CreateSyntaxError(S.Line, S.Col, S.Token, S.TokenString);
}
default:
{
Expression t = GetExpression();
Accept(SEMI);
return(t);
}
}
}
//c
private BlockExpression BlockStatements()
{
List <Expression> stats = new List <Expression>();
while (true)
{
switch (S.Token) // }
{
case RBRACE: // }
case EOF:
return(Expression.Block(stats));
case LBRACE: // {
case IF: // if
case FOR: // for
case WHILE: // while
case DO: // do
case RETURN: //return
case BREAK: //break;
case CONTINUE:
stats.Add(Statement());
break;
case LOCAL:
S.NextToken();
if (S.Token == IDENTIFIER)
{
stats.Add(VariableDeclaratorsRest(Ident()));
}
else if (S.Token == FUNCTION)
{
S.NextToken();
stats.Add(E.At(S.Pos).LocalVarDef(Ident(), MethodDeclaratorRest()));
}
else
{
throw ScriptCompileException.CreateSyntaxError(S.Line, S.Col, S.Token, S.TokenString);
}
Accept(SEMI);
break;
case FUNCTION:
S.NextToken();
functionList.Add(E.At(S.Pos).MethodDef(Ident(), MethodDeclaratorRest()));
break;
default:
Expression t = Term(EXPR | TYPE);
Contract.Assert(t != null);
stats.Add(t);
Accept(SEMI);
break;
}
}
}
