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

```
<lexer>
```
```
  <config>
```
```
    <name>Metal</name>
```
```
    <alias>metal</alias>
```
```
    <filename>*.metal</filename>
```

    <mime_type>text/x-metal</mime_type>

```
    <ensure_nl>true</ensure_nl>
```
```
  </config>
```
```
  <rules>
```
```
    <state name="function">
```
```
      <rule>
```
```
        <include state="whitespace"/>
```
```
      </rule>
```
```
      <rule>
```
```
        <include state="statements"/>
```
```
      </rule>
```
```
      <rule pattern=";">
```
```
        <token type="Punctuation"/>
```
```
      </rule>
```
```
      <rule pattern="\{">
```
```
        <token type="Punctuation"/>
```
```
        <push/>
```
```
      </rule>
```
```
      <rule pattern="\}">
```
```
        <token type="Punctuation"/>
```
```
        <pop depth="1"/>
```
```
      </rule>
```
```
    </state>
```
```
    <state name="macro">
```

      <rule pattern="(include)(\s*(?:/[*].*?[*]/\s*)?)([^\n]+)">

```
        <bygroups>
```

          <token type="CommentPreproc"/>

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

          <token type="CommentPreprocFile"/>

```
        </bygroups>
```
```
      </rule>
```
```
      <rule pattern="[^/\n]+">
```
```
        <token type="CommentPreproc"/>
```
```
      </rule>
```

      <rule pattern="/[*](.|\n)*?[*]/">

        <token type="CommentMultiline"/>

```
      </rule>
```
```
      <rule pattern="//.*?\n">
```
```
        <token type="CommentSingle"/>
```
```
        <pop depth="1"/>
```
```
      </rule>
```
```
      <rule pattern="/">
```
```
        <token type="CommentPreproc"/>
```
```
      </rule>
```
```
      <rule pattern="(?&lt;=\\)\n">
```
```
        <token type="CommentPreproc"/>
```
```
      </rule>
```
```
      <rule pattern="\n">
```
```
        <token type="CommentPreproc"/>
```
```
        <pop depth="1"/>
```
```
      </rule>
```
```
    </state>
```
```
    <state name="if0">
```

      <rule pattern="^\s*#if.*?(?&lt;!\\)\n">

```
        <token type="CommentPreproc"/>
```
```
        <push/>
```
```
      </rule>
```

      <rule pattern="^\s*#el(?:se|if).*\n">

```
        <token type="CommentPreproc"/>
```
```
        <pop depth="1"/>
```
```
      </rule>
```

      <rule pattern="^\s*#endif.*?(?&lt;!\\)\n">

```
        <token type="CommentPreproc"/>
```
```
        <pop depth="1"/>
```
```
      </rule>
```
```
      <rule pattern=".*?\n">
```
```
        <token type="Comment"/>
```
```
      </rule>
```
```
    </state>
```
```
    <state name="statements">
```

      <rule pattern="(namespace|constexpr|operator|template|using|this)\b">

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

      <rule pattern="(enum)\b(\s+)(class)\b(\s*)">

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

      <rule pattern="(class|struct|enum|union)\b(\s*)">

```
        <bygroups>
```
```
          <token type="Keyword"/>
```
```
          <token type="Text"/>
```
```
        </bygroups>
```
```
        <push state="classname"/>
```
```
      </rule>
```
```
      <rule pattern="\[\[.+\]\]">
```
```
        <token type="NameAttribute"/>
```
```
      </rule>
```

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

        <token type="LiteralNumberFloat"/>

```
      </rule>
```

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

        <token type="LiteralNumberFloat"/>

```
      </rule>
```

      <rule pattern="0[xX]([0-9A-Fa-f](&#39;?[0-9A-Fa-f]+)*)[LlUu]*">

        <token type="LiteralNumberHex"/>

```
      </rule>
```

      <rule pattern="0(&#39;?[0-7]+)+[LlUu]*">

        <token type="LiteralNumberOct"/>

```
      </rule>
```

      <rule pattern="0[Bb][01](&#39;?[01]+)*[LlUu]*">

        <token type="LiteralNumberBin"/>

```
      </rule>
```

      <rule pattern="[0-9](&#39;?[0-9]+)*[LlUu]*">

        <token type="LiteralNumberInteger"/>

```
      </rule>
```
```
      <rule pattern="\*/">
```
```
        <token type="Error"/>
```
```
      </rule>
```

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

```
        <token type="Operator"/>
```
```
      </rule>
```
```
      <rule pattern="[()\[\],.]">
```
```
        <token type="Punctuation"/>
```
```
      </rule>
```

      <rule pattern="(continue|typedef|sizeof|extern|static|switch|struct|return|union|const|break|while|enum|else|case|for|do|if)\b">

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

      <rule pattern="(bool|float|half|long|ptrdiff_t|size_t|unsigned|u?char|u?int((8|16|32|64)_t)?|u?short)\b">

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

      <rule pattern="(bool|float|half|u?(char|int|long|short))(2|3|4)\b">

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

      <rule pattern="packed_(float|half|long|u?(char|int|short))(2|3|4)\b">

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

      <rule pattern="(float|half)(2|3|4)x(2|3|4)\b">

```
        <token type="KeywordType"/>
```
```
      </rule>
```
```
      <rule pattern="atomic_u?int\b">
```
```
        <token type="KeywordType"/>
```
```
      </rule>
```

      <rule pattern="(rg?(8|16)(u|s)norm|rgba(8|16)(u|s)norm|srgba8unorm|rgb10a2|rg11b10f|rgb9e5)\b">

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

      <rule pattern="(array|depth(2d|cube)(_array)?|depth2d_ms(_array)?|sampler|texture_buffer|texture(1|2)d(_array)?|texture2d_ms(_array)?|texture3d|texturecube(_array)?|uniform|visible_function_table)\b">

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

      <rule pattern="(true|false|NULL)\b">

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

      <rule pattern="(threadgroup_imageblock|threadgroup|constant|ray_data|device|thread)\b">

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

      <rule pattern="([a-zA-Z_]\w*)(\s*)(:)(?!:)">

```
        <bygroups>
```
```
          <token type="NameLabel"/>
```
```
          <token type="Text"/>
```
```
          <token type="Punctuation"/>
```
```
        </bygroups>
```
```
      </rule>
```
```
      <rule pattern="[a-zA-Z_]\w*">
```
```
        <token type="Name"/>
```
```
      </rule>
```
```
    </state>
```
```
    <state name="root">
```
```
      <rule>
```
```
        <include state="whitespace"/>
```
```
      </rule>
```

      <rule pattern="(fragment|kernel|vertex)?((?:[\w*\s])+?(?:\s|[*]))([a-zA-Z_]\w*)(\s*\([^;]*?\))([^;{]*)(\{)">

```
        <bygroups>
```
```
          <token type="Keyword"/>
```
```
          <usingself state="root"/>
```
```
          <token type="NameFunction"/>
```
```
          <usingself state="root"/>
```
```
          <usingself state="root"/>
```
```
          <token type="Punctuation"/>
```
```
        </bygroups>
```
```
        <push state="function"/>
```
```
      </rule>
```

      <rule pattern="(fragment|kernel|vertex)?((?:[\w*\s])+?(?:\s|[*]))([a-zA-Z_]\w*)(\s*\([^;]*?\))([^;]*)(;)">

```
        <bygroups>
```
```
          <token type="Keyword"/>
```
```
          <usingself state="root"/>
```
```
          <token type="NameFunction"/>
```
```
          <usingself state="root"/>
```
```
          <usingself state="root"/>
```
```
          <token type="Punctuation"/>
```
```
        </bygroups>
```
```
      </rule>
```
```
      <rule>
```
```
        <push state="statement"/>
```
```
      </rule>
```
```
    </state>
```
```
    <state name="classname">
```

      <rule pattern="(\[\[.+\]\])(\s*)">

```
        <bygroups>
```

          <token type="NameAttribute"/>

```
          <token type="Text"/>
```
```
        </bygroups>
```
```
      </rule>
```
```
      <rule pattern="[a-zA-Z_]\w*">
```
```
        <token type="NameClass"/>
```
```
        <pop depth="1"/>
```
```
      </rule>
```
```
      <rule pattern="\s*(?=[&gt;{])">
```
```
        <token type="Text"/>
```
```
        <pop depth="1"/>
```
```
      </rule>
```
```
    </state>
```
```
    <state name="whitespace">
```
```
      <rule pattern="^#if\s+0">
```
```
        <token type="CommentPreproc"/>
```
```
        <push state="if0"/>
```
```
      </rule>
```
```
      <rule pattern="^#">
```
```
        <token type="CommentPreproc"/>
```
```
        <push state="macro"/>
```
```
      </rule>
```

      <rule pattern="^(\s*(?:/[*].*?[*]/\s*)?)(#if\s+0)">

```
        <bygroups>
```
```
          <usingself state="root"/>
```

          <token type="CommentPreproc"/>

```
        </bygroups>
```
```
        <push state="if0"/>
```
```
      </rule>
```

      <rule pattern="^(\s*(?:/[*].*?[*]/\s*)?)(#)">

```
        <bygroups>
```
```
          <usingself state="root"/>
```

          <token type="CommentPreproc"/>

```
        </bygroups>
```
```
        <push state="macro"/>
```
```
      </rule>
```
```
      <rule pattern="\n">
```
```
        <token type="Text"/>
```
```
      </rule>
```
```
      <rule pattern="\s+">
```
```
        <token type="Text"/>
```
```
      </rule>
```
```
      <rule pattern="\\\n">
```
```
        <token type="Text"/>
```
```
      </rule>
```

      <rule pattern="//(\n|[\w\W]*?[^\\]\n)">

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

      <rule pattern="/(\\\n)?[*][\w\W]*?[*](\\\n)?/">

        <token type="CommentMultiline"/>

```
      </rule>
```

      <rule pattern="/(\\\n)?[*][\w\W]*">

        <token type="CommentMultiline"/>

```
      </rule>
```
```
    </state>
```
```
    <state name="statement">
```
```
      <rule>
```
```
        <include state="whitespace"/>
```
```
      </rule>
```
```
      <rule>
```
```
        <include state="statements"/>
```
```
      </rule>
```
```
      <rule pattern="[{]">
```
```
        <token type="Punctuation"/>
```
```
        <push state="root"/>
```
```
      </rule>
```
```
      <rule pattern="[;}]">
```
```
        <token type="Punctuation"/>
```
```
        <pop depth="1"/>
```
```
      </rule>
```
```
    </state>
```
```
  </rules>
```
```
</lexer>
```