YamlDotNet.Core.Scanner.ScanTag C# (CSharp) Method

        Token ScanTag()
        {
            var start = cursor.Mark();

            // Check if the tag is in the canonical form.

            string handle;
            string suffix;

            if (analyzer.Check('<', 1))
            {
                // Set the handle to ''

                handle = string.Empty;

                // Eat '!<'

                Skip();
                Skip();

                // Consume the tag value.

                suffix = ScanTagUri(null, start);

                // Check for '>' and eat it.

                if (!analyzer.Check('>'))
                {
                    throw new SyntaxErrorException(start, cursor.Mark(), "While scanning a tag, did not find the expected '>'.");
                }

                Skip();
            }
            else
            {
                // The tag has either the '!suffix' or the '!handle!suffix' form.

                // First, try to scan a handle.

                var firstPart = ScanTagHandle(false, start);

                // Check if it is, indeed, handle.

                if (firstPart.Length > 1 && firstPart[0] == '!' && firstPart[firstPart.Length - 1] == '!')
                {
                    handle = firstPart;

                    // Scan the suffix now.

                    suffix = ScanTagUri(null, start);
                }
                else
                {
                    // It wasn't a handle after all.  Scan the rest of the tag.

                    suffix = ScanTagUri(firstPart, start);

                    // Set the handle to '!'.

                    handle = "!";

                    // A special case: the '!' tag.  Set the handle to '' and the
                    // suffix to '!'.

                    if (suffix.Length == 0)
                    {
                        suffix = handle;
                        handle = string.Empty;
                    }
                }
            }

            // Check the character which ends the tag.

            if (!analyzer.IsWhiteBreakOrZero())
            {
                throw new SyntaxErrorException(start, cursor.Mark(), "While scanning a tag, did not find expected whitespace or line break.");
            }

            // Create a token.

            return new Tag(handle, suffix, start, cursor.Mark());
        }