/// <summary>
/// Overloaded Parse function to parse a Function
/// </summary>
/// <param name="walker">Lexer input</param>
/// <returns></returns>
public IParseNode Parse(TokenWalker walker)
{
var lexem = walker.Pop();
if (lexem.Token is IdentifierToken)
{
FunctionNode function = new FunctionNode(lexem);
// Pop opening parenthesis
function.OpenParenthesis = walker.Consume <OpenParenthesisToken>();
function.Parameters.Add(_expressionParser.Parse(walker));
while (walker.NextIs <CommaToken>())
{
walker.Consume <CommaToken>();
function.Parameters.Add(_expressionParser.Parse(walker));
}
function.ClosedParenthesis = walker.Consume <ClosedParenthesisToken>();
return(function);
}
throw new ArgumentNullException();
}
/// <summary>
/// Overloaded Parse function to parse a Factor
/// </summary>
/// <param name="walker">Lexer input</param>
/// <returns></returns>
public IParseNode Parse(TokenWalker walker)
{
if (walker.NextIs <NumberToken>())
{
return(CreateNumberNode(walker));
}
if (walker.NextIs <IdentifierToken>())
{
return(walker.NextIs <OpenParenthesisToken>(1)
? _functionParser.Parse(walker)
: _variableParser.Parse(walker));
}
walker.ExpectOpeningParenthesis();
var result = _expressionParser.Parse(walker);
walker.ExpectClosingParenthesis();
return(result);
}
