1// Set these to how you want inline and display math to be delimited.
 2var defaultCopyDelimiters = {
 3  inline: ['$', '$'],
 4  // alternative: ['\(', '\)']
 5  display: ['$$', '$$'] // alternative: ['\[', '\]']
 6
 7}; // Replace .katex elements with their TeX source (<annotation> element).
 8// Modifies fragment in-place.  Useful for writing your own 'copy' handler,
 9// as in copy-tex.js.
10
11var katexReplaceWithTex = function katexReplaceWithTex(fragment, copyDelimiters) {
12  if (copyDelimiters === void 0) {
13    copyDelimiters = defaultCopyDelimiters;
14  }
15
16  // Remove .katex-html blocks that are preceded by .katex-mathml blocks
17  // (which will get replaced below).
18  var katexHtml = fragment.querySelectorAll('.katex-mathml + .katex-html');
19
20  for (var i = 0; i < katexHtml.length; i++) {
21    var element = katexHtml[i];
22
23    if (element.remove) {
24      element.remove(null);
25    } else {
26      element.parentNode.removeChild(element);
27    }
28  } // Replace .katex-mathml elements with their annotation (TeX source)
29  // descendant, with inline delimiters.
30
31
32  var katexMathml = fragment.querySelectorAll('.katex-mathml');
33
34  for (var _i = 0; _i < katexMathml.length; _i++) {
35    var _element = katexMathml[_i];
36
37    var texSource = _element.querySelector('annotation');
38
39    if (texSource) {
40      if (_element.replaceWith) {
41        _element.replaceWith(texSource);
42      } else {
43        _element.parentNode.replaceChild(texSource, _element);
44      }
45
46      texSource.innerHTML = copyDelimiters.inline[0] + texSource.innerHTML + copyDelimiters.inline[1];
47    }
48  } // Switch display math to display delimiters.
49
50
51  var displays = fragment.querySelectorAll('.katex-display annotation');
52
53  for (var _i2 = 0; _i2 < displays.length; _i2++) {
54    var _element2 = displays[_i2];
55    _element2.innerHTML = copyDelimiters.display[0] + _element2.innerHTML.substr(copyDelimiters.inline[0].length, _element2.innerHTML.length - copyDelimiters.inline[0].length - copyDelimiters.inline[1].length) + copyDelimiters.display[1];
56  }
57
58  return fragment;
59};
60
61document.addEventListener('copy', function (event) {
62  var selection = window.getSelection();
63
64  if (selection.isCollapsed) {
65    return; // default action OK if selection is empty
66  }
67
68  var fragment = selection.getRangeAt(0).cloneContents();
69
70  if (!fragment.querySelector('.katex-mathml')) {
71    return; // default action OK if no .katex-mathml elements
72  } // Preserve usual HTML copy/paste behavior.
73
74
75  var html = [];
76
77  for (var i = 0; i < fragment.childNodes.length; i++) {
78    html.push(fragment.childNodes[i].outerHTML);
79  }
80
81  event.clipboardData.setData('text/html', html.join('')); // Rewrite plain-text version.
82
83  event.clipboardData.setData('text/plain', katexReplaceWithTex(fragment).textContent); // Prevent normal copy handling.
84
85  event.preventDefault();
86});