private void EatBlanks(EOFCharEnumerator fen)
{
while (char.IsWhiteSpace(fen.Current) && fen.MoveNext())
{
;
}
}
public DynaFunction(string fdef)
{
Variables = new List <VarDef> ();
var fen = new EOFCharEnumerator(fdef);
FunctionName = UntilSeparator(fen, "(", "function");
EatBlanks(fen);
if (fen.PeekNext() == ')') // NO ARGUMENTS FUNCTION
{
fen.MoveNext();
}
else
{
while (fen.Current != ')')
{
var tmpVarName = UntilSeparator(fen, ":", "variable name");
if (!ExConst.ValidVarName(tmpVarName))
{
throw new ExpressionException("Invalid name for variable " + tmpVarName);
}
var tmpType = UntilSeparator(fen, ",)", "variable type");
if (Enum.TryParse(tmpType.ToUpperInvariant(), out DFDataType tmpDFDataType))
{
Variables.Add(new VarDef(tmpVarName, tmpDFDataType));
}
else
{
throw new ExpressionException("Invalid data type for variable " + tmpVarName + ": " + tmpType);
}
}
}
EatUntil(fen, ':');
var tmprettype = UntilSeparator(fen, "=", "return type");
if (!Enum.TryParse(tmprettype.ToUpperInvariant(), out DFDataType rettype))
{
throw new ExpressionException("Invalid return type: " + tmprettype);
}
ReturnType = rettype;
fen.MoveNext();
if (fen.Current != '>')
{
throw new ExpressionException("Unexpected character: " + fen.Current);
}
var exp = new StringBuilder();
while (fen.MoveNext())
{
exp.Append(fen.Current);
}
StringExpression = exp.ToString().Trim();
if (string.IsNullOrEmpty(StringExpression))
{
throw new ExpressionException("Empty expression");
}
new Expression().Parse(StringExpression);
}
private void EatUntil(EOFCharEnumerator fen, char sep)
{
while (fen.MoveNext() && fen.Current != sep)
{
if (!char.IsWhiteSpace(fen.Current))
{
throw new ExpressionException("Unexpected char: " + fen.Current);
}
}
}
private string UntilSeparator(EOFCharEnumerator f, string sep, string what)
{
StringBuilder name = new StringBuilder();
while (f.MoveNext() && sep.IndexOf(f.Current) < 0)
{
name.Append(f.Current);
}
string ret = name.ToString().Trim();
if (string.IsNullOrEmpty(ret))
{
throw new ExpressionException("Invalid syntax: empty " + what + " name");
}
foreach (char c in ret)
{
if (char.IsWhiteSpace(c))
{
throw new ExpressionException("Invalid function syntax: unexpected whitespace in " + what + " name");
}
}
return(ret);
}
