/// <summary>
/// constructor
/// </summary>
/// <param name="type"></param>
public Expression(int type)
{
m_type = type;
m_leftExp = null;
m_rightExp = null;
m_funcParams = null;
}
/// <summary>
/// constructor
/// </summary>
/// <param name="bd"></param>
public Expression(BaseData bd)
{
m_type = Expression.VALUE;
m_leftExp = null;
m_rightExp = null;
m_funcParams = null;
m_value = bd;
}
protected Expression expression7()
{
Expression exp = null;
int tt = lookAhead();
Token tok = null;
if (tt == Token.SYMBOL)
{
if (lookAhead(1) == Token.LEFT_PAREN)
{
// array
exp = new Expression(Expression.EXP_ARRAY_SYMBOL);
tok = eatToken(Token.SYMBOL);
exp.m_symbolName = tok.m_strVal;
eatToken(Token.LEFT_PAREN);
exp.m_funcParams = expressList();
eatToken(Token.RIGHT_PAREN);
}
else
{
exp = new Expression(Expression.EXP_SYMBOL);
tok = eatToken(Token.SYMBOL);
exp.m_symbolName = tok.m_strVal;
}
}
else if (tt == Token.INT)
{
tok = eatToken(Token.INT);
exp = new Expression(new BaseData(tok.m_intVal));
}
else if (tt == Token.FLOAT)
{
tok = eatToken(Token.FLOAT);
exp = new Expression(new BaseData(tok.m_floatVal));
}
else if (tt == Token.LEFT_PAREN)
{
eatToken(Token.LEFT_PAREN);
exp = expression();
eatToken(Token.RIGHT_PAREN);
}
else if( tt == Token.MINUS)
{
exp = new Expression(Expression.OP_NEG);
eatToken(Token.MINUS);
exp.m_leftExp = expression7();
}
else if( tt == Token.FUNC )
{
exp = new Expression(Expression.EXP_FUNC);
exp.m_funcParams = new List<Expression>();
// function name
tok = eatToken(Token.FUNC);
exp.m_symbolName = tok.m_strVal;
// function parameters
eatToken(Token.LEFT_PAREN);
exp.m_funcParams.Add( expression() );
while( lookAhead() == Token.COMMA )
{
eatToken(Token.COMMA);
exp.m_funcParams.Add(expression());
}
eatToken(Token.RIGHT_PAREN);
}
else if(tt == Token.STRING)
{
tok = eatToken(Token.STRING);
exp = new Expression(new BaseData(tok.m_strVal));
}
else if( tt == Token.FN)
{
exp = new Expression(Expression.EXP_USER_FUNC);
eatToken(Token.FN);
tok = eatToken(Token.SYMBOL);
exp.m_symbolName = tok.m_strVal;
eatToken(Token.LEFT_PAREN);
exp.m_funcParams = new List<Expression>();
exp.m_funcParams.Add(expression());
eatToken(Token.RIGHT_PAREN);
}
else if( tt == Token.INKEY )
{
exp = new Expression(Expression.EXP_INKEY);
eatToken(Token.INKEY);
}
else
{
throw new ErrorCode(ErrorCode.ERROR_CODE_02);
}
return exp;
}
protected Expression expression6()
{
Expression exp = expression7();
int tt = lookAhead();
while( tt == Token.POWER )
{
eatToken(Token.POWER);
Expression subExp = new Expression(Expression.OP_POWER);
subExp.m_leftExp = exp;
subExp.m_rightExp = expression7();
exp = subExp;
tt = lookAhead();
}
return exp;
}
protected Expression expression5()
{
Expression exp = expression6();
int tt = lookAhead();
while (tt == Token.MUL || tt == Token.DIV)
{
Expression subExp = null;
eatToken(tt);
if (tt == Token.MUL)
subExp = new Expression(Expression.OP_MUL);
else if (tt == Token.DIV)
subExp = new Expression(Expression.OP_DIV);
subExp.m_leftExp = exp;
subExp.m_rightExp = expression6();
exp = subExp;
tt = lookAhead();
}
return exp;
}
protected Expression expression4()
{
Expression exp = expression5();
int tt = lookAhead();
while (tt == Token.PLUS || tt == Token.MINUS)
{
Expression subExp = null;
eatToken(tt);
if (tt == Token.PLUS)
subExp = new Expression(Expression.OP_ADD);
else if (tt == Token.MINUS)
subExp = new Expression(Expression.OP_MINUS);
subExp.m_leftExp = exp;
subExp.m_rightExp = expression5();
exp = subExp;
tt = lookAhead();
}
return exp;
}
protected Expression expression3()
{
Expression exp = expression4();
int tt = lookAhead();
while( tt == Token.EQUAL || tt == Token.GTR || tt == Token.LT || tt == Token.GTE || tt == Token.LTE )
{
Expression subExp = null;
eatToken( tt );
if( tt == Token.EQUAL )
subExp = new Expression(Expression.OP_EQUAL);
else if( tt == Token.GTR )
subExp = new Expression(Expression.OP_GREATER);
else if( tt == Token.GTE)
subExp = new Expression(Expression.OP_GREATER_EQU);
else if( tt == Token.LT)
subExp = new Expression(Expression.OP_LESS);
else if( tt == Token.LTE)
subExp = new Expression(Expression.OP_LESS_EQ);
subExp.m_leftExp = exp;
subExp.m_rightExp = expression4();
exp = subExp;
tt = lookAhead();
}
return exp;
}
protected Expression expression2()
{
Expression exp = null;
Expression subExp = null;
int tt = lookAhead();
// NOT at the first
while( tt == Token.NOT )
{
eatToken(tt);
subExp = new Expression(Expression.OP_NOT);
if (exp != null)
subExp.m_leftExp = exp;
exp = subExp;
tt = lookAhead();
}
if (exp != null)
{
subExp = exp;
while( subExp.m_leftExp != null )
{
subExp = subExp.m_leftExp;
}
subExp.m_leftExp = expression3();
}
else
{
exp = expression3();
}
return exp;
}
/// <summary>
/// parse expression
/// </summary>
/// <returns></returns>
protected Expression expression()
{
Expression exp = expression2();
int tt = lookAhead();
while( tt == Token.AND || tt == Token.OR )
{
Expression subExp = null;
eatToken(tt);
if (tt == Token.AND)
subExp = new Expression(Expression.OP_AND);
else if (tt == Token.OR)
subExp = new Expression(Expression.OP_OR);
subExp.m_leftExp = exp;
subExp.m_rightExp = expression2();
exp = subExp;
tt = lookAhead();
}
return exp;
}
/// <summary>
/// for statement
/// </summary>
/// <returns></returns>
protected Statement forBegin()
{
Statement forS = new Statement(Statement.TYPE_FOR_BEGIN);
forS.m_expressList = new List<Expression>();
// keyword
eatToken(Token.FOR);
// loop var
Token tok = eatToken(Token.SYMBOL);
string symbolName = tok.m_strVal;
forS.m_symbol = symbolName;
if (symbolName.EndsWith("%"))
throw new ErrorCode(ErrorCode.ERROR_CODE_02);
else if (symbolName.EndsWith("$"))
throw new ErrorCode(ErrorCode.ERROR_CODE_12);
// equal
eatToken(Token.EQUAL);
// start number
forS.m_expressList.Add(expression());
// to
eatToken(Token.TO);
// end number
forS.m_expressList.Add(expression());
// if has step or not ?
int t = lookAhead();
if( t == Token.STEP )
{
eatToken(Token.STEP);
forS.m_expressList.Add(expression());
}
else
{
// default step
Expression step = new Expression(new BaseData(1));
forS.m_expressList.Add(step);
}
return forS;
}
protected int expInkeyCount( Expression exp )
{
if (exp.m_type == Expression.EXP_INKEY)
return 1;
int cnt = 0;
if (exp.m_leftExp != null)
cnt += expInkeyCount(exp.m_leftExp);
if (exp.m_rightExp != null)
cnt += expInkeyCount(exp.m_rightExp);
if( exp.m_funcParams != null )
{
foreach (Expression e in exp.m_funcParams)
cnt += expInkeyCount(e);
}
return cnt;
}
/// <summary>
/// replace symbol name in the expression
/// </summary>
/// <param name="exp"></param>
protected void replaceSymbolName( Expression exp, string oldName, string newName )
{
if ( exp.m_type == Expression.EXP_SYMBOL && exp.m_symbolName == oldName)
exp.m_symbolName = newName;
if( exp.m_funcParams != null)
{
foreach (Expression e in exp.m_funcParams)
replaceSymbolName(e, oldName, newName);
}
if (exp.m_leftExp != null)
replaceSymbolName(exp.m_leftExp, oldName, newName);
if (exp.m_rightExp != null)
replaceSymbolName(exp.m_rightExp, oldName, newName);
}
/// <summary>
/// reduce the expession
/// </summary>
/// <param name="exp"></param>
/// <returns></returns>
protected Expression calculateExp( Expression exp )
{
Expression result = null;
Expression midExp = null;
Expression expLeft = null;
Expression expRight = null;
switch( exp.m_type )
{
case Expression.VALUE:
result = exp;
break;
case Expression.TYPE_CLOSE_TO:
result = exp;
result.m_value = new BaseData(BaseData.TYPE_CLOSE_TO, 0);
break;
case Expression.TYPE_NEXT_LINE:
result = exp;
result.m_value = new BaseData(BaseData.TYPE_NEXT_LINE, 0);
break;
case Expression.EXP_SYMBOL:
VarSymbol s = m_symbolTable.ResolveVar(exp.m_symbolName);
result = new Expression( s.VALUE );
break;
case Expression.EXP_ARRAY_SYMBOL:
List<int> indexs = expressListToIndexs(exp.m_funcParams);
ArraySymbol arr = m_symbolTable.ResolveArray(exp.m_symbolName, indexs);
result = new Expression(arr.GetValue(indexs));
break;
// 内置函数
case Expression.EXP_FUNC:
List<BaseData> param = new List<BaseData>();
// convert the parameters
foreach (Expression e in exp.m_funcParams)
param.Add( calculateExp(e).m_value );
// call the function
BaseData returnVal = m_innerFunc.CallFunc(exp.m_symbolName, param);
result = new Expression(returnVal);
break;
// 用户自定义函数
case Expression.EXP_USER_FUNC:
string funcName = exp.m_symbolName;
FunSymbol func = m_symbolTable.ResolveFunc(funcName);
Expression funcParam = exp.m_funcParams[0];
BaseData paramVal = calculateExp(funcParam).m_value;
m_symbolTable.Define(new VarSymbol(CommonDef.FN_PARAM_SYMBOL, paramVal));
result = calculateExp(func.EXP);
break;
case Expression.OP_NOT:
midExp = calculateExp( exp.m_leftExp );
if( midExp.m_type == Expression.VALUE )
{
if (midExp.m_value != BaseData.ZERO)
result = new Expression( new BaseData(0) );
else
result = new Expression( new BaseData(1) );
}
else
{
throw new ErrorCode(ErrorCode.ERROR_CODE_12);
}
break;
case Expression.OP_NEG:
midExp = calculateExp(exp.m_leftExp);
if (midExp.m_type == Expression.VALUE)
{
result = midExp;
result.m_value.NegValue();
}
else
{
throw new ErrorCode(ErrorCode.ERROR_CODE_12);
}
break;
case Expression.EXP_INKEY:
result = new Expression(new BaseData(m_apiCall.Inkey()));
break;
// 二元运算符
case Expression.OP_ADD:
case Expression.OP_MINUS:
case Expression.OP_MUL:
case Expression.OP_DIV:
case Expression.OP_POWER:
case Expression.OP_AND:
case Expression.OP_OR:
case Expression.OP_EQUAL:
case Expression.OP_GREATER:
case Expression.OP_GREATER_EQU:
case Expression.OP_LESS:
case Expression.OP_LESS_EQ:
// check the value
expLeft = calculateExp(exp.m_leftExp);
expRight = calculateExp(exp.m_rightExp);
if (expLeft.m_type != Expression.VALUE || expRight.m_type != Expression.VALUE)
throw new ErrorCode(ErrorCode.ERROR_CODE_12);
if( exp.m_type == Expression.OP_ADD )
result = new Expression(expLeft.m_value + expRight.m_value);
else if( exp.m_type == Expression.OP_MINUS )
result = new Expression(expLeft.m_value - expRight.m_value);
else if( exp.m_type == Expression.OP_MUL)
result = new Expression(expLeft.m_value * expRight.m_value);
else if( exp.m_type == Expression.OP_DIV)
result = new Expression(expLeft.m_value / expRight.m_value);
else if( exp.m_type == Expression.OP_POWER)
result = new Expression(expLeft.m_value ^ expRight.m_value);
else if( exp.m_type == Expression.OP_AND)
result = new Expression(expLeft.m_value & expRight.m_value);
else if( exp.m_type == Expression.OP_OR)
result = new Expression(expLeft.m_value | expRight.m_value);
else if( exp.m_type == Expression.OP_EQUAL)
result = new Expression(expLeft.m_value == expRight.m_value ? 1 : 0 );
else if( exp.m_type == Expression.OP_GREATER)
result = new Expression( new BaseData( expLeft.m_value > expRight.m_value ? 1 : 0 ) );
else if( exp.m_type == Expression.OP_GREATER_EQU)
result = new Expression( new BaseData( expLeft.m_value >= expRight.m_value ? 1 : 0 ) );
else if( exp.m_type == Expression.OP_LESS)
result = new Expression(new BaseData(expLeft.m_value < expRight.m_value ? 1 : 0));
else if( exp.m_type == Expression.OP_LESS_EQ)
result = new Expression(new BaseData(expLeft.m_value <= expRight.m_value ? 1 : 0));
break;
default:
throw new ErrorCode(ErrorCode.ERROR_CODE_02);
}
return result;
}
/// <summary>
/// constrcutor
/// </summary>
/// <param name="exp"></param>
public WhileRecord( Expression exp, int beginIndex )
{
m_judgeExp = exp;
m_beginIndex = beginIndex;
}
/// <summary>
/// default constructor
/// </summary>
public Expression()
{
m_leftExp = null;
m_rightExp = null;
m_funcParams = null;
}
/// <summary>
/// constructor
/// </summary>
/// <param name="type"></param>
/// <param name="name"></param>
/// <param name="exp"></param>
public FunSymbol( string name, Expression exp )
{
m_type = Symbol.FUNC;
m_name = name;
m_exp = exp;
}
