public static ImmutableList <ParserChar> ToParserChar(this IEnumerable <char> input) { int line = 1; int col = 1; var list = new List <ParserChar>(); foreach (var c in input) { if (c == '\r') { continue; } list.Add(new ParserChar(c, SrcLoc.Return(line, col))); if (c == '\n') { line++; col = 1; } col++; } return(new ImmutableList <ParserChar>(list)); }