How to use the pygments.token.Name.Variable function in Pygments

bygroups(Keyword, Name), 'token-sym-brackets'),
            (r'(regex|token|rule)(?!' + PERL6_IDENTIFIER_RANGE + ')(\s*' + PERL6_IDENTIFIER_RANGE + '+)?',
             bygroups(Keyword, Name), 'pre-token'),
            # deal with a special case in the Perl 6 grammar (role q { ... })
            (r'(role)(\s+)(q)(\s*)', bygroups(Keyword, Text, Name, Text)),
            (_build_word_match(PERL6_KEYWORDS, PERL6_IDENTIFIER_RANGE), Keyword),
            (_build_word_match(PERL6_BUILTIN_CLASSES, PERL6_IDENTIFIER_RANGE, suffix='(?::[UD])?'),
             Name.Builtin),
            (_build_word_match(PERL6_BUILTINS, PERL6_IDENTIFIER_RANGE), Name.Builtin),
            # copied from PerlLexer
            (r'[$@%&][.^:?=!~]?' + PERL6_IDENTIFIER_RANGE + u'+(?:<<.*?>>|<.*?>|«.*?»)*',
             Name.Variable),
            (r'\$[!/](?:<<.*?>>|<.*?>|«.*?»)*', Name.Variable.Global),
            (r'::\?\w+', Name.Variable.Global),
            (r'[$@%&]\*' + PERL6_IDENTIFIER_RANGE + u'+(?:<<.*?>>|<.*?>|«.*?»)*',
             Name.Variable.Global),
            (r'\$(?:<.*?>)+', Name.Variable),
            (r'(?:q|qq|Q)[a-zA-Z]?\s*(?P:[\w\s:]+)?\s*(?P(?P[^0-9a-zA-Z:\s])'
             r'(?P=first_char)*)', brackets_callback(String)),
            # copied from PerlLexer
            (r'0_?[0-7]+(_[0-7]+)*', Number.Oct),
            (r'0x[0-9A-Fa-f]+(_[0-9A-Fa-f]+)*', Number.Hex),
            (r'0b[01]+(_[01]+)*', Number.Bin),
            (r'(?i)(\d*(_\d*)*\.\d+(_\d*)*|\d+(_\d*)*\.\d+(_\d*)*)(e[+-]?\d+)?',
             Number.Float),
            (r'(?i)\d+(_\d*)*e[+-]?\d+(_\d*)*', Number.Float),
            (r'\d+(_\d+)*', Number.Integer),
            (r'(?<=~~)\s*/(?:\\\\|\\/|.)*?/', String.Regex),
            (r'(?<=[=(,])\s*/(?:\\\\|\\/|.)*?/', String.Regex),
            (r'm\w+(?=\()', Name),
            (r'(?:m|ms|rx)\s*(?P:[\w\s:]+)?\s*(?P(?P[^\w:\s])'
             r'(?P=first_char)*)', brackets_callback(String.Regex)),

(r'#\d+#', Operator),

            # read-time comment
            (r'#+nil' + terminated + '\s*\(', Comment.Preproc, 'commented-form'),

            # read-time conditional
            (r'#[+-]', Operator),

            # special operators that should have been parsed already
            (r'(,@|,|\.)', Operator),

            # special constants
            (r'(t|nil)' + terminated, Name.Constant),

            # functions and variables
            (r'\*' + symbol + '\*', Name.Variable.Global),
            (symbol, Name.Variable),

            # parentheses
            (r'\(', Punctuation, 'body'),
            (r'\)', Punctuation, '#pop'),
        ],
    }


class HaskellLexer(RegexLexer):
    """
    A Haskell lexer based on the lexemes defined in the Haskell 98 Report.

    *New in Pygments 0.8.*
    """
    name = 'Haskell'

(r'^([-+])(\s*)'                         # method marker
                 r'(\(.*?\))?(\s*)'                      # return type
                 r'([a-zA-Z$_][\w$]*:?)',        # begin of method name
                 bygroups(Punctuation, Text, using(this),
                          Text, Name.Function),
                 'method'),
                inherit,
            ],
            'method': [
                include('whitespace'),
                # TODO unsure if ellipses are allowed elsewhere, see
                # discussion in Issue 789
                (r',', Punctuation),
                (r'\.\.\.', Punctuation),
                (r'(\(.*?\))(\s*)([a-zA-Z$_][\w$]*)',
                 bygroups(using(this), Text, Name.Variable)),
                (r'[a-zA-Z$_][\w$]*:', Name.Function),
                (';', Punctuation, '#pop'),
                (r'\{', Punctuation, 'function'),
                default('#pop'),
            ],
            'literal_number': [
                (r'\(', Punctuation, 'literal_number_inner'),
                (r'\)', Literal, '#pop'),
                include('statement'),
            ],
            'literal_number_inner': [
                (r'\(', Punctuation, '#push'),
                (r'\)', Punctuation, '#pop'),
                include('statement'),
            ],
            'literal_array': [

(r'^([-+])(\s*)'                         # method marker
                 r'(\(.*?\))?(\s*)'                      # return type
                 r'([a-zA-Z$_][\w$]*:?)',        # begin of method name
                 bygroups(Punctuation, Text, using(this),
                          Text, Name.Function),
                 'method'),
                inherit,
            ],
            'method': [
                include('whitespace'),
                # TODO unsure if ellipses are allowed elsewhere, see
                # discussion in Issue 789
                (r',', Punctuation),
                (r'\.\.\.', Punctuation),
                (r'(\(.*?\))(\s*)([a-zA-Z$_][\w$]*)',
                 bygroups(using(this), Text, Name.Variable)),
                (r'[a-zA-Z$_][\w$]*:', Name.Function),
                (';', Punctuation, '#pop'),
                (r'\{', Punctuation, 'function'),
                default('#pop'),
            ],
            'literal_number': [
                (r'\(', Punctuation, 'literal_number_inner'),
                (r'\)', Literal, '#pop'),
                include('statement'),
            ],
            'literal_number_inner': [
                (r'\(', Punctuation, '#push'),
                (r'\)', Punctuation, '#pop'),
                include('statement'),
            ],
            'literal_array': [

'more/local': [
            (r',', Punctuation, 'main/local'),
            include('more')
        ],
        # List
        'more/list': [
            (r'[,:]', Punctuation, 'main'),
            include('more')
        ],
        # Parameter list
        'main/parameters': [
            (r'(%s)(%s*)(?=:)' % (_name, _ws),
             bygroups(Name.Variable, using(this, state='whitespace')), '#pop'),
            (r'(%s)(%s+)(%s)' % (_name, _ws, _name),
             bygroups(Name.Class, using(this, state='whitespace'),
                      Name.Variable), '#pop'),
            (r'\[+', Punctuation),
            include('main/basic'),
            (_name, Name.Variable, '#pop'),
            default('#pop')
        ],
        'more/parameters': [
            (r'(:)(%s*(?=[?=,:)]))' % _ws,
             bygroups(Punctuation, using(this, state='whitespace'))),
            (r'[?\]]+', Punctuation),
            (r'[:)]', Punctuation, ('#pop', 'multimethod?')),
            (r',', Punctuation, 'main/parameters'),
            (r'=', Punctuation, ('more/parameter', 'main')),
            include('more')
        ],
        'more/parameter': [
            (r'(?=[,)])', Text, '#pop'),

datatype = (
        r'\b(address|bool|(?:(?:bytes|hash|int|string|uint)(?:8|16|24|32|40|48|56|64'
        r'|72|80|88|96|104|112|120|128|136|144|152|160|168|176|184|192|200|208'
        r'|216|224|232|240|248|256)?))\b'
    )

    tokens = {
        'root': [
            include('whitespace'),
            include('comments'),
            (r'\bpragma\s+solidity\b', Keyword, 'pragma'),
            (r'\b(contract)(\s+)([a-zA-Z_]\w*)',
             bygroups(Keyword, Whitespace, Name.Entity)),
            (datatype + r'(\s+)((?:external|public|internal|private)\s+)?' +
             r'([a-zA-Z_]\w*)',
             bygroups(Keyword.Type, Whitespace, Keyword, Name.Variable)),
            (r'\b(enum|event|function|struct)(\s+)([a-zA-Z_]\w*)',
             bygroups(Keyword.Type, Whitespace, Name.Variable)),
            (r'\b(msg|block|tx)\.([A-Za-z_][a-zA-Z0-9_]*)\b', Keyword),
            (words((
                'block', 'break', 'constant', 'constructor', 'continue',
                'contract', 'do', 'else', 'external', 'false', 'for',
                'function', 'if', 'import', 'inherited', 'internal', 'is',
                'library', 'mapping', 'memory', 'modifier', 'msg', 'new',
                'payable', 'private', 'public', 'require', 'return',
                'returns', 'struct', 'suicide', 'throw', 'this', 'true',
                'tx', 'var', 'while'), prefix=r'\b', suffix=r'\b'),
             Keyword.Type),
            (words(('keccak256',), prefix=r'\b', suffix=r'\b'), Name.Builtin),
            (datatype, Keyword.Type),
            include('constants'),
            (r'[a-zA-Z_]\w*', Text),

(r'/\*(.|\n)*?\*/', Comment),
        ],
        'root': [
            include('whitespace'),
            include('comments'),

            (r'(lexer|parser|tree)?(\s*)(grammar\b)(\s*)(' + _id + ')(;)',
             bygroups(Keyword, Whitespace, Keyword, Whitespace, Name.Class,
                      Punctuation)),
            # optionsSpec
            (r'options\b', Keyword, 'options'),
            # tokensSpec
            (r'tokens\b', Keyword, 'tokens'),
            # attrScope
            (r'(scope)(\s*)(' + _id + ')(\s*)(\{)',
             bygroups(Keyword, Whitespace, Name.Variable, Whitespace,
                      Punctuation), 'action'),
            # exception
            (r'(catch|finally)\b', Keyword, 'exception'),
            # action
            (r'(@' + _id + ')(\s*)(::)?(\s*)(' + _id + ')(\s*)(\{)',
             bygroups(Name.Label, Whitespace, Punctuation, Whitespace,
                      Name.Label, Whitespace, Punctuation), 'action'),
            # rule
            (r'((?:protected|private|public|fragment)\b)?(\s*)(' + _id + ')(!)?',
             bygroups(Keyword, Whitespace, Name.Label, Punctuation),
             ('rule-alts', 'rule-prelims')),
        ],
        'exception': [
            (r'\n', Whitespace, '#pop'),
            (r'\s', Whitespace),
            include('comments'),

tokens = {
        'root': [
            include('whitespace'),

            # Before keywords, because keywords are valid label names :(...
            (identifier + '\s*:', Name.Label),

            include('keyword'),

            (r'%' + identifier, Name.Variable),
            (r'@' + identifier, Name.Variable.Global),
            (r'%\d+', Name.Variable.Anonymous),
            (r'@\d+', Name.Variable.Global),
            (r'#\d+', Name.Variable.Global),
            (r'!' + identifier, Name.Variable),
            (r'!\d+', Name.Variable.Anonymous),
            (r'c?' + string, String),

            (r'0[xX][a-fA-F0-9]+', Number),
            (r'-?\d+(?:[.]\d+)?(?:[eE][-+]?\d+(?:[.]\d+)?)?', Number),

            (r'[=<>{}\[\]()*.,!]|x\b', Punctuation)
        ],
        'whitespace': [
            (r'(\n|\s)+', Text),
            (r';.*?\n', Comment)
        ],
        'keyword': [
            # Regular keywords
            (r'(begin|end'
             r'|true|false'
             r'|declare|define'

(r'(?:default|datatypes)\b', Keyword.Declaration),
            (r'##.*$', Comment.Preproc),
            (r'#.*$', Comment.Single),
            (r'"[^"]*"', String.Double),
            # TODO single quoted strings and escape sequences outside of
            # double-quoted strings
            (r'(?:element|attribute|mixed)\b', Keyword.Declaration, 'variable'),
            (r'(text\b|xsd:[^ ]+)', Keyword.Type, 'maybe_xsdattributes'),
            (r'[,?&*=|~]|>>', Operator),
            (r'[(){}]', Punctuation),
            (r'.', Text),
        ],

        # a variable has been declared using `element` or `attribute`
        'variable': [
            (r'[^{]+', Name.Variable),
            (r'\{', Punctuation, '#pop'),
        ],

        # after an xsd: declaration there may be attributes
        'maybe_xsdattributes': [
            (r'\{', Punctuation, 'xsdattributes'),
            (r'\}', Punctuation, '#pop'),
            (r'.', Text),
        ],

        # attributes take the form { key1 = value1 key2 = value2 ... }
        'xsdattributes': [
            (r'[^ =}]', Name.Attribute),
            (r'=', Operator),
            (r'"[^"]*"', String.Double),
            (r'\}', Punctuation, '#pop'),

def _process_signature(self, tokens):
        for index, token, value in tokens:
            if token == Literal and value == '}':
                yield index, Punctuation, value
                raise StopIteration
            elif token in (Literal, Name.Function):
                token = Name.Variable if value.istitle() else Keyword.Type
            yield index, token, value