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node_modules/katex/contrib/copy-tex/README.md

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+# Copy-tex extension
+
+This extension modifies the copy/paste behavior in any browser supporting the
+[Clipboard API](https://developer.mozilla.org/en-US/docs/Web/API/ClipboardEvent)
+so that, when selecting and copying KaTeX-rendered elements, the text
+content of the resulting clipboard renders KaTeX elements as their LaTeX source
+surrounded by specified delimiters.  (The HTML content of the resulting
+clipboard remains the selected HTML content, as it normally would.)
+The default delimiters are `$...$` for inline math and `$$...$$` for display
+math, but you can easy switch them to e.g. `\(...\)` and `\[...\]` by
+modifying `copyDelimiters` in [the source code](copy-tex.js).
+Note that a selection containing part of a KaTeX formula gets extended to
+include the entire KaTeX formula.
+
+## Usage
+
+This extension isn't part of KaTeX proper, so the script should be separately
+included in the page.
+
+```html
+<script src="https://cdn.jsdelivr.net/npm/katex@0.16.23/dist/contrib/copy-tex.min.js" integrity="sha384-HORx6nWi8j5/mYA+y57/9/CZc5z8HnEw4WUZWy5yOn9ToKBv1l58vJaufFAn9Zzi" crossorigin="anonymous"></script>
+```
+
+(Note that, as of KaTeX 0.16.0, there is no longer a corresponding CSS file.)
+
+See [index.html](index.html) for an example.
+(To run this example from a clone of the repository, run `yarn start`
+in the root KaTeX directory, and then visit
+http://localhost:7936/contrib/copy-tex/index.html
+with your web browser.)
+
+If you want to build your own custom copy handler based on this one,
+copy the `copy-tex.js` into your codebase and replace the `require`
+statement with `require('katex/contrib/copy-tex/katex2tex.js')`.
+
+ECMAScript module is also available:
+```html
+<script type="module" src="https://cdn.jsdelivr.net/npm/katex@0.16.23/dist/contrib/copy-tex.mjs" integrity="sha384-bVEnwt0PtX+1EuJoOEcm4rgTUWvb2ILTdjHfI1gUe/r5fdqrTcQaUuRdHG2DciuQ" crossorigin="anonymous"></script>
+```