private Expr ValueToExpr(Type t, object newValue)
{
if (t == typeof(int))
{
IntVal intVal = new IntVal();;
intVal.Value = Convert.ToInt32(newValue);
return(intVal);
}
else if (t == typeof(float))
{
FloatVal floatVal = new FloatVal();
floatVal.Value = Convert.ToSingle(newValue);
return(floatVal);
}
else if (t == typeof(double))
{
DoubleVal doubleVal = new DoubleVal();
doubleVal.Value = Convert.ToDouble(newValue);
return(doubleVal);
}
else if (t == typeof(decimal))
{
DecimalVal decimalVal = new DecimalVal();
decimalVal.Value = Convert.ToDecimal(newValue);
return(decimalVal);
}
else if (t == typeof(string))
{
StringVal stringVal = new StringVal();
stringVal.Value = Convert.ToString(newValue);
return(stringVal);
}
else if (t == typeof(DateTime))
{
DateTimeVal dateTimeVal = new DateTimeVal();
dateTimeVal.Value = Convert.ToDateTime(newValue);
return(dateTimeVal);
}
else if (t == typeof(bool))
{
BoolVal boolVal = new BoolVal();
boolVal.Value = Convert.ToBoolean(newValue);
return(boolVal);
}
else
{
StringVal stringVal = new StringVal();
stringVal.Value = Convert.ToString(newValue);
return(stringVal);
}
}
private Expr ParseFactor()
{
if (this.index == this.tokens.Count)
{
throw new System.Exception("expected expression, got EOF");
}
if (this.tokens[this.index] is StringToken)
{
StringVal stringLiteral = new StringVal();
stringLiteral.Value = ((StringToken)this.tokens[this.index]).Value;
MoveNext();
return(stringLiteral);
}
else if (this.tokens[this.index] is IntToken)
{
IntVal intVal = new IntVal();
intVal.Value = ((IntToken)this.tokens[this.index]).Value;
MoveNext();
return(intVal);
}
else if (this.tokens[this.index] is FloatToken)
{
FloatVal floVal = new FloatVal();
floVal.Value = ((FloatToken)this.tokens[this.index]).Value;
MoveNext();
return(floVal);
}
else if (this.tokens[this.index] is DoubleToken)
{
DoubleVal douVal = new DoubleVal();
douVal.Value = ((DoubleToken)this.tokens[this.index]).Value;
MoveNext();
return(douVal);
}
else if (this.tokens[this.index] is DecimalToken)
{
DecimalVal decVal = new DecimalVal();
decVal.Value = ((DecimalToken)this.tokens[this.index]).Value;
MoveNext();
return(decVal);
}
else if (this.tokens[this.index] is DateTimeToken)
{
DateTimeVal datVal = new DateTimeVal();
datVal.Value = ((DateTimeToken)this.tokens[this.index]).Value;
MoveNext();
return(datVal);
}
else if (this.tokens[this.index] is BoolToken)
{
BoolVal bolVal = new BoolVal();
bolVal.Value = ((BoolToken)this.tokens[this.index]).Value;
MoveNext();
return(bolVal);
}
else if (this.tokens[this.index] == Tokens.Null)
{
NullVal nullVal = new NullVal();
MoveNext();
return(nullVal);
}
else if (this.tokens[this.index] is IdentifierToken)
{
string ident = ((IdentifierToken)tokens[index]).Name;
MoveNext();
// function expr
if (MaybeEat(Tokens.LeftBracket))
{
FunctionExpr fun = new FunctionExpr();
fun = ParseFunction(ident);
return(fun);
}
// variable
else
{
Variable var = new Variable();
var.Ident = ident;
return(var);
}
}
else if (this.tokens[this.index] == Tokens.New)
{
MoveNext(); // eat new
return(ParseNewObject());
}
else if (this.tokens[this.index] == Tokens.LeftBracket)
{
// Eat LeftParenthesis
MoveNext();
Expr result = ParseExpr();
Eat(Tokens.RightBracket);
return(result);
}
else if (IsUnaryOperator(this.tokens[index]))
{
// Unary Expression
UnaryExpr result = new UnaryExpr();
if (MaybeEat(Tokens.Sub))
{
result.Op = TokenToBinOp(Tokens.Sub);
}
else if (MaybeEat(Tokens.Add))
{
result.Op = TokenToBinOp(Tokens.Add);
}
else if (MaybeEat(Tokens.Not))
{
result.Op = TokenToBinOp(Tokens.Not);
}
else
{
throw new System.Exception(string.Format(
"Operator '{0}' is not supported in unary expressions",
tokens[index]));
}
result.Expression = ParseFactor();
return(result);
}
else
{
throw new System.Exception("expected string literal, numeric literal, or variable");
}
}
