math-in-rust-doc 0.1.0

Demo of add math to rust doc
Documentation
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<script src="https://cdn.jsdelivr.net/npm/katex@0.10.0/dist/katex.min.js"                  integrity="sha384-K3vbOmF2BtaVai+Qk37uypf7VrgBubhQreNQe9aGsz9lB63dIFiQVlJbr92dw2Lx" crossorigin="anonymous"></script>

<script>
  "use strict";
  document.addEventListener("DOMContentLoaded", function () {
      var maths = document.getElementsByClassName("language-math");
      for (var i=0; i<maths.length; i++) {
          var el = maths[i];
          katex.render(el.innerText, el, {displayMode: true});
      }

      var codes = document.getElementsByTagName("code");
      for (i=0; i<codes.length; i++) {
          el = codes[i];
          if (el.classList.contains("language-math")) continue;
          if (el.classList.contains("language-inline-math")) {
              katex.render(el.innerText, el);
              continue;
          }

          var parent = el.parentNode;
          if (parent.nodeName.toLowerCase() === "pre") continue;
          // TODO: Can this be done with DOM manipulation rather than string manipulation?
          // https://stackoverflow.com/q/48438067/3019990
          var inlineMath = "$" + el.outerHTML + "$";
          if (parent.innerHTML.indexOf(inlineMath) !== -1) {
              el.classList.add("language-inline-math");
              parent.innerHTML = parent.innerHTML.replace("$" + el.outerHTML + "$", el.outerHTML);
              i--;
          }
      }
  });
</script>