HTML5 MathML
HTML5 MathML <mfenced> Tag
The <mfenced> element automatically wraps its children in fences (brackets) with optional separators between them. It has been deprecated in favour of explicit <mo> operators, but you will still meet it in older documents.
Definition and Usage
<mfenced> saved authors from writing opening and closing bracket operators by hand. The open and close attributes set the bracket characters, and separators lists the characters placed between consecutive children.
Attributes
| Attribute | Description |
|---|---|
| open | The opening fence character (default is "("). |
| close | The closing fence character (default is ")"). |
| separators | Characters placed between children (default is a comma). |
Example
This renders an ordered pair inside parentheses. Since <mfenced> is deprecated, the second math block shows the recommended <mo> replacement.
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>MathML mfenced</title>
</head>
<body>
<p>Deprecated mfenced:</p>
<math display="block">
<mfenced open="(" close=")" separators=",">
<mi>x</mi>
<mi>y</mi>
</mfenced>
</math>
<p>Recommended replacement with mo:</p>
<math display="block">
<mrow>
<mo>(</mo>
<mi>x</mi><mo>,</mo><mi>y</mi>
<mo>)</mo>
</mrow>
</math>
</body>
</html><mfenced> is deprecated and not part of MathML Core. Prefer explicit <mo> fences (using the stretchy attribute where needed) for reliable rendering in Chrome, Edge, Firefox and Safari.
Key Takeaways
- <mfenced> auto-wraps children in brackets with separators.
- open, close and separators control the bracket and delimiter characters.
- It is deprecated - use <mo>(</mo> and <mo>)</mo> instead.