/*
* S -> [S] | ParamList
* ParamList -> [S] OptParams | NUM | NUM OptParams
* OptParams -> , ParamList | eps
* NUM -> int
*/
private static ArrayItem FromString(string str, ref int pos)
{
ArrayItem arrayItem = new ArrayItem();
if (str[pos] == '[')
{
++pos;
while (pos < str.Length && str[pos] != ']')
{
if (str[pos] == '[')
{
arrayItem.Items.Add(FromString(str, ref pos));
if (pos >= str.Length)
{
throw new ArgumentException($"Missing closing parenthesis at pos {str.Length - 1}");
}
if (str[pos] != ']')
{
throw new ArgumentException($"Missing closing parenthesis at pos {pos}");
}
++pos;
if (pos < str.Length && str[pos] == ',')
{
++pos;
}
}
else if (char.IsDigit(str[pos]))
{
Console.WriteLine("Processing number");
NumItem tmp = new NumItem();
while (pos < str.Length && char.IsDigit(str[pos]))
{
tmp.Value *= 10;
tmp.Value += int.Parse(str[pos].ToString());
++pos;
}
arrayItem.Items.Add(tmp);
if (pos < str.Length && str[pos] == ',')
{
++pos;
}
}
else
{
throw new ArgumentException($"Unexpected `{str[pos]}` got at pos {pos}");
}
}
if (pos >= str.Length && str[str.Length - 1] != ']')
{
throw new ArgumentException($"Missing closing parenthesis at pos {str.Length - 1}");
}
}
else
{
throw new ArgumentException($"Unexpected `{str[pos]}` got at pos {pos}");
}
return(arrayItem);
}
public static Item ListElementNTerm(string s, ref int pos)
{
Item item = new Item();
Console.WriteLine("ListElementNTerm");
if (s[pos] == '[')
{
item = ListNTerm(s, ref pos);
}
else if (char.IsDigit(s[pos]))
{
Console.WriteLine("Number encountered");
item = new NumItem();
while (pos < s.Length && char.IsDigit(s[pos]))
{
((NumItem)item).Value *= 10;
((NumItem)item).Value += int.Parse(s[pos].ToString());
++pos;
}
}
return(item);
}