private SyntaxTree ParseFactorOrFunctionCall()
{
SyntaxTree factor = null;
Token token = CurrentToken;
if (token.TokenType == TokenType.Identifier)
{
Match(TokenType.Identifier);
if (CurrentToken.TokenType == TokenType.OpenParenthesis)
{
Match(TokenType.OpenParenthesis);
FunctionCallTree functionCall = new FunctionCallTree(token);
functionCall.Arguments = ParseArgumentList();
Match(TokenType.CloseParenthesis);
factor = functionCall;
}
else
{
factor = new FactorTree(token);
}
}
else if (CurrentToken.TokenType == TokenType.Scalar)
{
Match(TokenType.Scalar);
factor = new FactorTree(token);
}
else
{
throw new ParserException(token, TokenType.Identifier, TokenType.Scalar);
}
return(factor);
}
protected virtual string EmitFactor(FactorTree factor)
{
StandardFunctionResolver resolver = new StandardFunctionResolver();
string src = string.Empty;
if (factor.Token.TokenType == TokenType.Identifier)
{
if (resolver.IsStandardVariable(factor.Token.Value))
{
src = resolver.ResolveToStandardVariableName(factor.Token.Value);
}
else if (factor.Token.Value == FunctionParameterName)
{
// refers to actual parameter of function, which will always be emitted as ___x
src = "___x";
}
else
{
src = string.Format(
"MathContext.Variables[\"{0}\"]",
factor.Token.Value
);
}
}
else
{
src = factor.Token.Value;
}
return(src);
}
protected virtual List <CodeErrorException> TypeCheckFactor(FactorTree factorTree)
{
List <CodeErrorException> errors = new List <CodeErrorException>();
// if identifier is function parameter then it's okay, otherwise make sure it's defined in variable
// context
if (factorTree.Token.TokenType == TokenType.Identifier)
{
if (factorTree.Token.Value != FunctionParameterName)
{
if (!MathContext.Variables.ContainsVariable(factorTree.Token.Value))
{
errors.Add(
new CodeErrorException(
factorTree.Token.Line,
factorTree.Token.StartPosition,
factorTree.Token.EndPosition,
string.Format(
"The variable '{0}' is not defined in math context",
factorTree.Token.Value
)
)
);
}
}
}
return(errors);
}