tartrazine/lexers/bnf.xml

<lexer>
  <config>
    <name>BNF</name>
    <alias>bnf</alias>
    <filename>*.bnf</filename>
    <mime_type>text/x-bnf</mime_type>
  </config>
  <rules>
    <state name="root">
      <rule pattern="(&lt;)([ -;=?-~]+)(&gt;)">
        <bygroups>
          <token type="Punctuation"/>
          <token type="NameClass"/>
          <token type="Punctuation"/>
        </bygroups>
      </rule>
      <rule pattern="::=">
        <token type="Operator"/>
      </rule>
      <rule pattern="[^&lt;&gt;:]+">
        <token type="Text"/>
      </rule>
      <rule pattern=".">
        <token type="Text"/>
      </rule>
    </state>
  </rules>
</lexer>