public void TestAdvancedTokeniser()
{
IdfTokeniser tks = new IdfTokeniser();
tks.ParseTokens("one + two * three - andsoe(p1, p2, p3) + (1 + 5-6/7)");
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Literal);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Operator);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Literal);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Operator);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Literal);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Operator);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Function);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.LeftParen);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Literal);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.ParamSeperator);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Literal);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.ParamSeperator);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Literal);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.RightParen);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Operator);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.LeftParen);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Literal);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Operator);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Literal);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Operator);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Literal);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Operator);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Literal);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.RightParen);
Assert.AreEqual(tks.PeekToken(), null);
;
}
public void TestBasicTokeniser()
{
IdfTokeniser tks = new IdfTokeniser();
tks.ParseTokens("one + two * three");
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Literal);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Operator);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Literal);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Operator);
Assert.AreEqual(tks.NextToken().Type, IdfTokenType.Literal);
}
/// <summary>
/// Compile a IDF string
/// </summary>
/// <param name="str">The IDF string</param>
/// <returns>The Compiled IDF</returns>
public string Compile(string str)
{
//find equals and just send the right side to the tokeniser
int eqIndex = str.IndexOf('=');
_assignee = str.Substring(0, eqIndex).Trim();
//TODO: check no white space inside assignee
string right = str.Substring(eqIndex+1, str.Length - eqIndex-1);
IdfTokeniser tk = new IdfTokeniser();
tk.ParseTokens(right);
//Check our tokenised equation for validity
CheckSyntaxRules(tk);
CheckFunctionRules(tk);
//convert to RPN and return as compile IDF
return GenerateOutput(ShuntingYard(tk));
}
/// <summary>
/// Convert infix to Reverse Polish Notation
/// </summary>
/// <param name="tks">IdfTokeniser that has parsed its tokens already</param>
/// <returns></returns>
private Queue<IdfToken> ShuntingYard(IdfTokeniser tks)
{
Stack<IdfToken> stack = new Stack<IdfToken>();
Queue<IdfToken> output = new Queue<IdfToken>();
IdfToken tk = null;
//reset the tokeniser to the start of its list
tks.Reset();
//see wikipeia Shunting Yard Article for details
while (tks.PeekToken() != null)
{
tk = tks.NextToken();
switch (tk.Type)
{
case IdfTokenType.Literal:
output.Enqueue(tk);
break;
case IdfTokenType.Function:
stack.Push(tk);
break;
case IdfTokenType.ParamSeperator:
while (stack.Peek().Type != IdfTokenType.LeftParen)
{
output.Enqueue(stack.Pop());
if (stack.Count == 0)
{
throw new IdfParseException("Mismatched parens or bad param separator");
}
}
break;
case IdfTokenType.Operator:
if (stack.Count != 0)
{
while (stack.Peek().Type == IdfTokenType.Operator)
{
if ((tk.Operator.Precedence < stack.Peek().Operator.Precedence) || (tk.Operator.Associativity == Associativity.Left && tk.Operator.Precedence <= stack.Peek().Operator.Precedence))
{
output.Enqueue(stack.Pop());
}
else
{
break;
}
if (stack.Count == 0)
break;
}
}
stack.Push(tk);
break;
case IdfTokenType.LeftParen:
stack.Push(tk);
break;
case IdfTokenType.RightParen:
while (stack.Peek().Type != IdfTokenType.LeftParen)
{
output.Enqueue(stack.Pop());
if (stack.Count == 0)
{
throw new IdfParseException("Mismatched parens");
}
}
stack.Pop();
if (stack.Count != 0)
{
if (stack.Peek().Type == IdfTokenType.Function)
{
output.Enqueue(stack.Pop());
}
}
break;
}
}
while (stack.Count != 0)
{
if (stack.Peek().Type == IdfTokenType.LeftParen || stack.Peek().Type == IdfTokenType.RightParen)
{
throw new IdfParseException("Mismatched parens");
}
output.Enqueue(stack.Pop());
}
return output;
}
/// <summary>
/// Check basic syntax rules
/// </summary>
/// <param name="tokeniser"></param>
private void CheckSyntaxRules(IdfTokeniser tokeniser)
{
//TODO: implementation
}
/// <summary>
/// Check that all the functions have the right number of parameters
/// Check that literals dont have function names
/// </summary>
/// <param name="tokeniser"></param>
private void CheckFunctionRules(IdfTokeniser tokeniser)
{
//TODO: implementation
}