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diff --git a/pygments/lexers/grammar_notation.py b/pygments/lexers/grammar_notation.py
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+# -*- coding: utf-8 -*-
+"""
+    pygments.lexers.grammar_notation
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+    Lexers for grammer notations like BNF.
+
+    :copyright: Copyright 2006-2015 by the Pygments team, see AUTHORS.
+    :license: BSD, see LICENSE for details.
+"""
+
+from pygments.lexer import RegexLexer, bygroups, words
+from pygments.token import Punctuation, Text, Comment, Operator, \
+    Keyword, Name, Literal
+
+__all__ = ['BnfLexer', 'AbnfLexer']
+
+
+class BnfLexer(RegexLexer):
+    """
+    This lexer is for grammer notations which are similar to
+    original BNF.
+
+    In order to maximize a number of targets of this lexer,
+    let's decide some designs:
+
+    * We don't distinguish `Terminal Symbol`.
+
+    * We do assume that `NonTerminal Symbol` are always enclosed
+      with arrow brackets.
+
+    * We do assume that `NonTerminal Symbol` may include
+      any printable characters except arrow brackets and ASCII 0x20.
+      This assumption is for `RBNF <http://www.rfc-base.org/txt/rfc-5511.txt>`_.
+
+    * We do assume that target notation doesn't support comment.
+
+    * We don't distinguish any operators and punctuation except
+      `::=`.
+
+    Though these desision making might cause too minimal highlighting
+    and you might be disappointed, but it is reasonable for us.
+
+    .. versionadded:: 2.1
+    """
+
+    name = 'BNF'
+    aliases = ['bnf']
+    filenames = ['*.bnf']
+    mimetypes = ['text/x-bnf']
+
+    tokens = {
+        'root': [
+            (r'(<)([ -;=?-~]+)(>)',
+             bygroups(Punctuation, Name.Class, Punctuation)),
+
+            # an only operator
+            (r'::=', Operator),
+
+            # fallback
+            (r'[^<>:]+', Text),  # for performance
+            (r'.', Text),
+        ],
+    }
+
+
+class AbnfLexer(RegexLexer):
+    """
+    Lexer for `IETF 7405 ABNF
+    <http://www.ietf.org/rfc/rfc7405.txt>`_
+    (Updates `5234 <http://www.ietf.org/rfc/rfc5234.txt>`_)
+    grammars.
+
+    .. versionadded:: 2.1
+    """
+
+    name = 'ABNF'
+    aliases = ['abnf']
+    filenames = ['*.abnf']
+    mimetypes = ['text/x-abnf']
+
+    _core_rules = (
+        'ALPHA', 'BIT', 'CHAR', 'CR', 'CRLF', 'CTL', 'DIGIT',
+        'DQUOTE', 'HEXDIG', 'HTAB', 'LF', 'LWSP', 'OCTET',
+        'SP', 'VCHAR', 'WSP')
+
+    tokens = {
+        'root': [
+            # comment
+            (r';.*$', Comment.Single),
+
+            # quoted
+            #   double quote itself in this state, it is as '%x22'.
+            (r'(%[si])?"[^"]*"', Literal),
+
+            # binary (but i have never seen...)
+            (r'%b[01]+\-[01]+\b', Literal),  # range
+            (r'%b[01]+(\.[01]+)*\b', Literal),  # concat
+
+            # decimal
+            (r'%d[0-9]+\-[0-9]+\b', Literal),  # range
+            (r'%d[0-9]+(\.[0-9]+)*\b', Literal),  # concat
+
+            # hexadecimal
+            (r'%x[0-9a-fA-F]+\-[0-9a-fA-F]+\b', Literal),  # range
+            (r'%x[0-9a-fA-F]+(\.[0-9a-fA-F]+)*\b', Literal),  # concat
+
+            # repetition (<a>*<b>element) including nRule
+            (r'\b[0-9]+\*[0-9]+', Operator),
+            (r'\b[0-9]+\*', Operator),
+            (r'\b[0-9]+', Operator),
+            (r'\*', Operator),
+
+            # Strictly speaking, these are not keyword but
+            # are called `Core Rule'.
+            (words(_core_rules, suffix=r'\b'), Keyword),
+
+            # nonterminals (ALPHA *(ALPHA / DIGIT / "-"))
+            (r'[a-zA-Z][a-zA-Z0-9-]+\b', Name.Class),
+
+            # operators
+            (r'(=/|=|/)', Operator),
+
+            # punctuation
+            (r'[\[\]()]', Punctuation),
+
+            # fallback
+            (r'\s+', Text),
+            (r'.', Text),
+        ],
+    }