Expr ParseExpr()
{
var OpStack = new Stack<Operator>();
var CStack = new Stack<Expr>();
ExprNext NextCanBe = ExprNext.UExpr | ExprNext.BExpr | ExprNext.Literal | ExprNext.Bracket;
while (Index < Tokens.Count)
{
// token is literal (double, int, bool, string, function call)
if (NextCanBe.HasFlag(ExprNext.Literal))
{
if (Tokens[Index].isSB)
{
var stringLiteral = new StringLiteral();
stringLiteral.Value = ((StringBuilder)Tokens[Index]).ToString();
Index++;
CStack.Push(stringLiteral);
NextCanBe = ExprNext.BExpr;
continue;
}
else if (Tokens[Index].isInt)
{
var intLiteral = new IntLiteral();
intLiteral.Value = (int)Tokens[Index];
Index++;
CStack.Push(intLiteral);
NextCanBe = ExprNext.BExpr;
continue;
}
else if (Tokens[Index].isDbl)
{
var dblLiteral = new DblLiteral();
dblLiteral.Value = (double)Tokens[Index];
NextCanBe = ExprNext.BExpr;
Index++;
CStack.Push(dblLiteral);
continue;
}
else if (Tokens[Index].isStr && FuncDef.ContainsKey((string)Tokens[Index]))
{ // If function is exists
var function = new ExprFunction();
function.Identity = (string)Tokens[Index];
var P = FuncDef[(string)Tokens[Index]].Parameters.Count;
int i = 0;
Index++;
while (Index < Tokens.Count && i < P)
{
function.Parameters.Add(ParseExpr());
i++;
}
if (Index == Tokens.Count && i < P)
{
throw new RPExeption(29, App.Current.TryFindResource("x_fparnm").ToString(), Line, Column);
}
CStack.Push(function);
NextCanBe = ExprNext.BExpr;
continue;
}
}
// if token is not expression either break
if (!NextCanBe.HasFlag(ExprNext.UExpr) && !NextCanBe.HasFlag(ExprNext.BExpr) && !NextCanBe.HasFlag(ExprNext.Bracket) || !Tokens[Index].isStr) break;
// else token is an operator
switch ((string)Tokens[Index])
{
case Scanner.BracketStart:
if (NextCanBe.HasFlag(ExprNext.Bracket))
{
Index++;
OpStack.Push(new Group());
NextCanBe = ExprNext.UExpr | ExprNext.BExpr | ExprNext.Literal | ExprNext.Bracket;
continue;
}
break;
case Scanner.BracketEnd:
{
Index++;
var o = (OpStack.Count > 0) ? OpStack.Peek() : null;
while (OpStack.Count > 0 && !(o is Group))
{
if (o.IsBinary)
{
var expr = new BinaryExpression();
expr.BinaryOperator = OpStack.Pop();
if (expr.BinaryOperator.Level >= OpStack.Peek().Level)
{
expr.Right = CStack.Pop();
expr.Left = CStack.Pop();
}
else
{
expr.Left = CStack.Pop();
expr.Right = CStack.Pop();
}
CStack.Push(expr);
}
else
{
var expr = new UnaryExpression();
expr.Right = CStack.Pop();
expr.UnaryOperator = OpStack.Pop();
CStack.Push(expr);
}
if (OpStack.Count > 0) o = OpStack.Peek();
}
if (OpStack.Count > 0)
{
OpStack.Pop();
NextCanBe = ExprNext.BExpr;
}
else NextCanBe = 0;
continue;
}
case Scanner.ValueOf:
if (NextCanBe.HasFlag(ExprNext.UExpr))
{
Index++;
var var = new Variable();
var.Identity = (string)Tokens[Index];
CStack.Push(var);
OpStack.Push(new ValueOf());
NextCanBe = ExprNext.BExpr;
Index++;
continue;
}
break;
case Scanner.AsIs:
if (NextCanBe.HasFlag(ExprNext.UExpr))
{
Index++;
var strL = new StringLiteral();
strL.Value = (string)Tokens[Index];
CStack.Push(strL);
OpStack.Push(new AsIs());
NextCanBe = ExprNext.BExpr;
Index++;
continue;
}
break;
case Scanner.And:
case Scanner.Or:
case Scanner.Xor:
case Scanner.Not:
case Scanner.Add:
case Scanner.Subtract:
case Scanner.Multiply:
case Scanner.Divide:
case Scanner.Equal:
case Scanner.Bigger:
case Scanner.BiggerEqual:
case Scanner.Smaller:
case Scanner.SmallerEqual:
case Scanner.NotEqual:
{
var op = Operator.Parse((string)Tokens[Index]);
var o = (OpStack.Count > 0) ? OpStack.Peek() : op;
while (OpStack.Count > 0 && op.Level >= o.Level && !(o is Group))
{
if (o.IsBinary)
{
var expr = new BinaryExpression();
expr.Right = CStack.Pop();
expr.BinaryOperator = OpStack.Pop();
expr.Left = CStack.Pop();
CStack.Push(expr);
}
else
{
var expr = new UnaryExpression();
expr.Right = CStack.Pop();
expr.UnaryOperator = OpStack.Pop();
CStack.Push(expr);
}
if (OpStack.Count > 0) o = OpStack.Peek();
}
if (CStack.Count == 0 && op is Sub || Diff(CStack, OpStack) && op is Sub) op = new Minus(); // If there was no literal before or previous token was also an operator
OpStack.Push(op);
NextCanBe = ExprNext.BExpr | ExprNext.UExpr | ExprNext.Literal | ExprNext.Bracket;
Index++;
continue;
}
}
break;
}
while (OpStack.Count > 0)
{
var o = OpStack.Peek();
if (o.IsBinary)
{
var expr = new BinaryExpression();
expr.Right = CStack.Pop();
expr.BinaryOperator = OpStack.Pop();
expr.Left = CStack.Pop();
CStack.Push(expr);
}
else
{
var expr = new UnaryExpression();
expr.Right = CStack.Pop();
expr.UnaryOperator = OpStack.Pop();
CStack.Push(expr);
}
}
return CStack.Pop();
}
Expr ParseExpr()
{
var OpStack = new Stack <Operator>();
var CStack = new Stack <Expr>();
ExprNext NextCanBe = ExprNext.UExpr | ExprNext.BExpr | ExprNext.Literal | ExprNext.Bracket;
while (Index < Tokens.Count)
{
// token is literal (double, int, bool, string, function call)
if (NextCanBe.HasFlag(ExprNext.Literal))
{
if (Tokens[Index].isSB)
{
var stringLiteral = new StringLiteral();
stringLiteral.Value = ((StringBuilder)Tokens[Index]).ToString();
Index++;
CStack.Push(stringLiteral);
NextCanBe = ExprNext.BExpr;
continue;
}
else if (Tokens[Index].isInt)
{
var intLiteral = new IntLiteral();
intLiteral.Value = (int)Tokens[Index];
Index++;
CStack.Push(intLiteral);
NextCanBe = ExprNext.BExpr;
continue;
}
else if (Tokens[Index].isDbl)
{
var dblLiteral = new DblLiteral();
dblLiteral.Value = (double)Tokens[Index];
NextCanBe = ExprNext.BExpr;
Index++;
CStack.Push(dblLiteral);
continue;
}
else if (Tokens[Index].isStr && FuncDef.ContainsKey((string)Tokens[Index]))
{ // If function is exists
var function = new ExprFunction();
function.Identity = (string)Tokens[Index];
var P = FuncDef[(string)Tokens[Index]].Parameters.Count;
int i = 0;
Index++;
while (Index < Tokens.Count && i < P)
{
function.Parameters.Add(ParseExpr());
i++;
}
if (Index == Tokens.Count && i < P)
{
throw new RPExeption(29, App.Current.TryFindResource("x_fparnm").ToString(), Line, Column);
}
CStack.Push(function);
NextCanBe = ExprNext.BExpr;
continue;
}
}
// if token is not expression either break
if (!NextCanBe.HasFlag(ExprNext.UExpr) && !NextCanBe.HasFlag(ExprNext.BExpr) && !NextCanBe.HasFlag(ExprNext.Bracket) || !Tokens[Index].isStr)
{
break;
}
// else token is an operator
switch ((string)Tokens[Index])
{
case Scanner.BracketStart:
if (NextCanBe.HasFlag(ExprNext.Bracket))
{
Index++;
OpStack.Push(new Group());
NextCanBe = ExprNext.UExpr | ExprNext.BExpr | ExprNext.Literal | ExprNext.Bracket;
continue;
}
break;
case Scanner.BracketEnd:
{
Index++;
var o = (OpStack.Count > 0) ? OpStack.Peek() : null;
while (OpStack.Count > 0 && !(o is Group))
{
if (o.IsBinary)
{
var expr = new BinaryExpression();
expr.BinaryOperator = OpStack.Pop();
if (expr.BinaryOperator.Level >= OpStack.Peek().Level)
{
expr.Right = CStack.Pop();
expr.Left = CStack.Pop();
}
else
{
expr.Left = CStack.Pop();
expr.Right = CStack.Pop();
}
CStack.Push(expr);
}
else
{
var expr = new UnaryExpression();
expr.Right = CStack.Pop();
expr.UnaryOperator = OpStack.Pop();
CStack.Push(expr);
}
if (OpStack.Count > 0)
{
o = OpStack.Peek();
}
}
if (OpStack.Count > 0)
{
OpStack.Pop();
NextCanBe = ExprNext.BExpr;
}
else
{
NextCanBe = 0;
}
continue;
}
case Scanner.ValueOf:
if (NextCanBe.HasFlag(ExprNext.UExpr))
{
Index++;
var var = new Variable();
var.Identity = (string)Tokens[Index];
CStack.Push(var);
OpStack.Push(new ValueOf());
NextCanBe = ExprNext.BExpr;
Index++;
continue;
}
break;
case Scanner.AsIs:
if (NextCanBe.HasFlag(ExprNext.UExpr))
{
Index++;
var strL = new StringLiteral();
strL.Value = (string)Tokens[Index];
CStack.Push(strL);
OpStack.Push(new AsIs());
NextCanBe = ExprNext.BExpr;
Index++;
continue;
}
break;
case Scanner.And:
case Scanner.Or:
case Scanner.Xor:
case Scanner.Not:
case Scanner.Add:
case Scanner.Subtract:
case Scanner.Multiply:
case Scanner.Divide:
case Scanner.Equal:
case Scanner.Bigger:
case Scanner.BiggerEqual:
case Scanner.Smaller:
case Scanner.SmallerEqual:
case Scanner.NotEqual:
{
var op = Operator.Parse((string)Tokens[Index]);
var o = (OpStack.Count > 0) ? OpStack.Peek() : op;
while (OpStack.Count > 0 && op.Level >= o.Level && !(o is Group))
{
if (o.IsBinary)
{
var expr = new BinaryExpression();
expr.Right = CStack.Pop();
expr.BinaryOperator = OpStack.Pop();
expr.Left = CStack.Pop();
CStack.Push(expr);
}
else
{
var expr = new UnaryExpression();
expr.Right = CStack.Pop();
expr.UnaryOperator = OpStack.Pop();
CStack.Push(expr);
}
if (OpStack.Count > 0)
{
o = OpStack.Peek();
}
}
if (CStack.Count == 0 && op is Sub || Diff(CStack, OpStack) && op is Sub)
{
op = new Minus(); // If there was no literal before or previous token was also an operator
}
OpStack.Push(op);
NextCanBe = ExprNext.BExpr | ExprNext.UExpr | ExprNext.Literal | ExprNext.Bracket;
Index++;
continue;
}
}
break;
}
while (OpStack.Count > 0)
{
var o = OpStack.Peek();
if (o.IsBinary)
{
var expr = new BinaryExpression();
expr.Right = CStack.Pop();
expr.BinaryOperator = OpStack.Pop();
expr.Left = CStack.Pop();
CStack.Push(expr);
}
else
{
var expr = new UnaryExpression();
expr.Right = CStack.Pop();
expr.UnaryOperator = OpStack.Pop();
CStack.Push(expr);
}
}
return(CStack.Pop());
}
