Viewing github.com/alecthomas/chroma/lexers/embedded/vhdl.xml

```
<lexer>
```
```
  <config>
```
```
    <name>VHDL</name>
```
```
    <alias>vhdl</alias>
```
```
    <filename>*.vhdl</filename>
```
```
    <filename>*.vhd</filename>
```
```
    <mime_type>text/x-vhdl</mime_type>
```

    <case_insensitive>true</case_insensitive>

```
  </config>
```
```
  <rules>
```
```
    <state name="root">
```
```
      <rule pattern="\n">
```
```
        <token type="Text"/>
```
```
      </rule>
```
```
      <rule pattern="\s+">
```
```
        <token type="Text"/>
```
```
      </rule>
```
```
      <rule pattern="\\\n">
```
```
        <token type="Text"/>
```
```
      </rule>
```
```
      <rule pattern="--.*?$">
```
```
        <token type="CommentSingle"/>
```
```
      </rule>
```

      <rule pattern="&#39;(U|X|0|1|Z|W|L|H|-)&#39;">

        <token type="LiteralStringChar"/>

```
      </rule>
```

      <rule pattern="[~!%^&amp;*+=|?:&lt;&gt;/-]">

```
        <token type="Operator"/>
```
```
      </rule>
```
```
      <rule pattern="&#39;[a-z_]\w*">
```
```
        <token type="NameAttribute"/>
```
```
      </rule>
```

      <rule pattern="[()\[\],.;\&#39;]">

```
        <token type="Punctuation"/>
```
```
      </rule>
```

      <rule pattern="&#34;[^\n\\&#34;]*&#34;">

```
        <token type="LiteralString"/>
```
```
      </rule>
```

      <rule pattern="(library)(\s+)([a-z_]\w*)">

```
        <bygroups>
```
```
          <token type="Keyword"/>
```
```
          <token type="Text"/>
```

          <token type="NameNamespace"/>

```
        </bygroups>
```
```
      </rule>
```

      <rule pattern="(use)(\s+)(entity)">

```
        <bygroups>
```
```
          <token type="Keyword"/>
```
```
          <token type="Text"/>
```
```
          <token type="Keyword"/>
```
```
        </bygroups>
```
```
      </rule>
```

      <rule pattern="(use)(\s+)([a-z_][\w.]*\.)(all)">

```
        <bygroups>
```
```
          <token type="Keyword"/>
```
```
          <token type="Text"/>
```

          <token type="NameNamespace"/>

```
          <token type="Keyword"/>
```
```
        </bygroups>
```
```
      </rule>
```

      <rule pattern="(use)(\s+)([a-z_][\w.]*)">

```
        <bygroups>
```
```
          <token type="Keyword"/>
```
```
          <token type="Text"/>
```

          <token type="NameNamespace"/>

```
        </bygroups>
```
```
      </rule>
```

      <rule pattern="(std|ieee)(\.[a-z_]\w*)">

```
        <bygroups>
```

          <token type="NameNamespace"/>

          <token type="NameNamespace"/>

```
        </bygroups>
```
```
      </rule>
```

      <rule pattern="(ieee|work|std)\b">

```
        <token type="NameNamespace"/>
```
```
      </rule>
```

      <rule pattern="(entity|component)(\s+)([a-z_]\w*)">

```
        <bygroups>
```
```
          <token type="Keyword"/>
```
```
          <token type="Text"/>
```
```
          <token type="NameClass"/>
```
```
        </bygroups>
```
```
      </rule>
```

      <rule pattern="(architecture|configuration)(\s+)([a-z_]\w*)(\s+)(of)(\s+)([a-z_]\w*)(\s+)(is)">

```
        <bygroups>
```
```
          <token type="Keyword"/>
```
```
          <token type="Text"/>
```
```
          <token type="NameClass"/>
```
```
          <token type="Text"/>
```
```
          <token type="Keyword"/>
```
```
          <token type="Text"/>
```
```
          <token type="NameClass"/>
```
```
          <token type="Text"/>
```
```
          <token type="Keyword"/>
```
```
        </bygroups>
```
```
      </rule>
```

      <rule pattern="([a-z_]\w*)(:)(\s+)(process|for)">

```
        <bygroups>
```
```
          <token type="NameClass"/>
```
```
          <token type="Operator"/>
```
```
          <token type="Text"/>
```
```
          <token type="Keyword"/>
```
```
        </bygroups>
```
```
      </rule>
```
```
      <rule pattern="(end)(\s+)">
```
```
        <bygroups>
```
```
          <token type="Keyword"/>
```
```
          <token type="Text"/>
```
```
        </bygroups>
```
```
        <push state="endblock"/>
```
```
      </rule>
```
```
      <rule>
```
```
        <include state="types"/>
```
```
      </rule>
```
```
      <rule>
```
```
        <include state="keywords"/>
```
```
      </rule>
```
```
      <rule>
```
```
        <include state="numbers"/>
```
```
      </rule>
```
```
      <rule pattern="[a-z_]\w*">
```
```
        <token type="Name"/>
```
```
      </rule>
```
```
    </state>
```
```
    <state name="endblock">
```
```
      <rule>
```
```
        <include state="keywords"/>
```
```
      </rule>
```
```
      <rule pattern="[a-z_]\w*">
```
```
        <token type="NameClass"/>
```
```
      </rule>
```
```
      <rule pattern="(\s+)">
```
```
        <token type="Text"/>
```
```
      </rule>
```
```
      <rule pattern=";">
```
```
        <token type="Punctuation"/>
```
```
        <pop depth="1"/>
```
```
      </rule>
```
```
    </state>
```
```
    <state name="types">
```

      <rule pattern="(std_ulogic_vector|file_open_status|std_logic_vector|severity_level|file_open_kind|delay_length|std_ulogic|bit_vector|character|std_logic|positive|unsigned|boolean|natural|integer|signed|string|time|bit)\b">

```
        <token type="KeywordType"/>
```
```
      </rule>
```
```
    </state>
```
```
    <state name="keywords">
```

      <rule pattern="(configuration|architecture|disconnect|attribute|transport|postponed|procedure|component|function|variable|severity|constant|generate|register|inertial|package|library|guarded|linkage|generic|subtype|process|literal|record|entity|others|shared|signal|downto|access|assert|return|reject|buffer|impure|select|elsif|inout|until|label|range|group|units|begin|array|alias|after|block|while|null|next|file|when|wait|open|nand|exit|then|case|port|type|loop|else|pure|with|xnor|body|not|rem|bus|rol|ror|xor|abs|end|and|sla|sll|sra|srl|all|out|nor|mod|map|for|new|use|or|on|of|in|if|is|to)\b">

```
        <token type="Keyword"/>
```
```
      </rule>
```
```
    </state>
```
```
    <state name="numbers">
```

      <rule pattern="\d{1,2}#[0-9a-f_]+#?">

        <token type="LiteralNumberInteger"/>

```
      </rule>
```
```
      <rule pattern="\d+">
```

        <token type="LiteralNumberInteger"/>

```
      </rule>
```

      <rule pattern="(\d+\.\d*|\.\d+|\d+)E[+-]?\d+">

        <token type="LiteralNumberFloat"/>

```
      </rule>
```

      <rule pattern="X&#34;[0-9a-f_]+&#34;">

        <token type="LiteralNumberHex"/>

```
      </rule>
```

      <rule pattern="O&#34;[0-7_]+&#34;">

        <token type="LiteralNumberOct"/>

```
      </rule>
```

      <rule pattern="B&#34;[01_]+&#34;">

        <token type="LiteralNumberBin"/>

```
      </rule>
```
```
    </state>
```
```
  </rules>
```
```
</lexer>
```