docs(v2): New doc page for math equations (#4821)

* New doc page for math equations

* improve math equations doc

Co-authored-by: slorber <lorber.sebastien@gmail.com>

website/docs/guides/markdown-features/markdown-features-math-equations.mdx

@@ -0,0 +1,119 @@
+---
+id: math-equations
+title: Math Equations
+description: Writing LaTeX Math Equations
+slug: /markdown-features/math-equations
+---
+
+Mathematical equations can be rendered using [KaTeX](https://katex.org).
+
+## Usage
+
+Please read [KaTeX](https://katex.org) documentation for more details.
+
+### Inline
+
+Write inline math equations by wrapping LaTeX equations between `$`:
+
+```mdx
+Let $f:[a,b] \to \R$ be Riemann integrable. Let $F:[a,b]\to\R$ be $F(x)=
+\int_{a}^{x}f(t)dt$. Then $$F$$ is continuous, and at all $x$ such that $f$ is continuous at $x$, $F$ is differentiable at $x$ with $F'(x)=f(x)$.
+```
+
+Let $f:[a,b] \to \R$ be Riemann integrable. Let $F:[a,b]\to\R$ be $F(x)=
+\int_{a}^{x}f(t)dt$. Then $F$ is continuous, and at all $x$ such that $f$ is continuous at $x$, $F$ is differentiable at $x$ with $F'(x)=f(x)$.
+
+### Blocks
+
+For equation block or display mode, use line breaks and `$$`:
+
+```mdx
+$$
+I = \int_0^{2\pi} \sin(x) dx
+$$
+```
+
+$$
+I = \int_0^{2\pi} \sin(x) dx
+$$
+
+## Configuration
+
+To enable KaTeX, you need to install `remark-math` and `rehype-katex` plugins.
+
+```bash npm2yarn
+npm install --save remark-math@3 rehype-katex@4 hast-util-is-element@1.1.0
+```
+
+:::caution
+
+Use the exact same versions. The latest versions are incompatible with Docusaurus 2.
+
+:::
+
+Import the plugins in `docusaurus.config.js`:
+
+```js
+const math = require('remark-math');
+const katex = require('rehype-katex');
+```
+
+Add them to your content plugin or preset options (usually `@docusaurus/preset-classic` docs options):
+
+```js
+remarkPlugins: [math],
+rehypePlugins: [katex],
+```
+
+Include the KaTeX CSS in your config under `stylesheets`:
+
+```js
+stylesheets: [
+    {
+        href: "https://cdn.jsdelivr.net/npm/katex@0.13.11/dist/katex.min.css",
+        type: "text/css",
+        integrity: "sha384-Um5gpz1odJg5Z4HAmzPtgZKdTBHZdw8S29IecapCSB31ligYPhHQZMIlWLYQGVoc",
+        crossorigin: "anonymous",
+    },
+],
+```
+
+Overall the changes look like:
+
+```diff title="docusaurus.config.js"
+// highlight-start
++ const math = require('remark-math');
++ const katex = require('rehype-katex');
+// highlight-end
+
+
+module.exports = {
+  title: 'Docusaurus',
+  tagline: 'Build optimized websites quickly, focus on your content',
+  presets: [
+    [
+      '@docusaurus/preset-classic',
+      {
+        docs: {
+          path: 'docs',
+          // highlight-start
++         remarkPlugins: [math],
++         rehypePlugins: [katex],
+          // highlight-end
+        },
+      },
+    ],
+  ],
+  // highlight-start
++ stylesheets: [
++   {
++     href: 'https://cdn.jsdelivr.net/npm/katex@0.13.11/dist/katex.min.css',
++     type: 'text/css',
++     integrity:
++       'sha384-Um5gpz1odJg5Z4HAmzPtgZKdTBHZdw8S29IecapCSB31ligYPhHQZMIlWLYQGVoc',
++     crossorigin: 'anonymous',
++   },
++ ],
+  // highlight-end
+};
+```

website/docusaurus.config.js

@@ -7,6 +7,8 @@
 
 const path = require('path');
 const versions = require('./versions.json');
+const math = require('remark-math');
+const katex = require('rehype-katex');
 
 // This probably only makes sense for the beta phase, temporary
 function getNextBetaVersionName() {
@@ -52,6 +54,15 @@ const isVersioningDisabled = !!process.env.DISABLE_VERSIONING || isI18nStaging;
   baseUrl,
   baseUrlIssueBanner: true,
   url: 'https://docusaurus.io',
+  stylesheets: [
+    {
+      href: 'https://cdn.jsdelivr.net/npm/katex@0.13.11/dist/katex.min.css',
+      type: 'text/css',
+      integrity:
+        'sha384-Um5gpz1odJg5Z4HAmzPtgZKdTBHZdw8S29IecapCSB31ligYPhHQZMIlWLYQGVoc',
+      crossorigin: 'anonymous',
+    },
+  ],
   i18n: {
     defaultLocale: 'en',
     locales: isDeployPreview
@@ -237,8 +248,10 @@ const isVersioningDisabled = !!process.env.DISABLE_VERSIONING || isI18nStaging;
           showLastUpdateAuthor: true,
           showLastUpdateTime: true,
           remarkPlugins: [
+            math,
             [require('@docusaurus/remark-plugin-npm2yarn'), {sync: true}],
           ],
+          rehypePlugins: [katex],
           disableVersioning: isVersioningDisabled,
           lastVersion: isDev ? 'current' : undefined,
           onlyIncludeVersions:

website/package.json

@@ -44,6 +44,9 @@
     "npm-to-yarn": "^1.0.0-2",
     "react": "^17.0.2",
     "react-dom": "^17.0.2",
+    "rehype-katex": "^4.0.0",
+    "remark-math": "^3.0.1",
+    "hast-util-is-element": "1.1.0",
     "workbox-routing": "^5.0.0",
     "workbox-strategies": "^5.0.0"
   },

website/sidebars.js

@@ -43,6 +43,7 @@ module.exports = {
             'guides/markdown-features/inline-toc',
             'guides/markdown-features/assets',
             'guides/markdown-features/plugins',
+            'guides/markdown-features/math-equations',
           ],
         },
         'styling-layout',

yarn.lock

@@ -3516,6 +3516,11 @@
   resolved "https://registry.yarnpkg.com/@types/json5/-/json5-0.0.29.tgz#ee28707ae94e11d2b827bcbe5270bcea7f3e71ee"
   integrity sha1-7ihweulOEdK4J7y+UnC86n8+ce4=
 
+"@types/katex@^0.11.0":
+  version "0.11.0"
+  resolved "https://registry.yarnpkg.com/@types/katex/-/katex-0.11.0.tgz#b16c54ee670925ffef0616beae9e90c557e17334"
+  integrity sha512-27BfE8zASRLYfSBNMk5/+KIjr2CBBrH0i5lhsO04fca4TGirIIMay73v3zNkzqmsaeIa/Mi5kejWDcxPLAmkvA==
+
 "@types/loader-utils@^2.0.2":
   version "2.0.2"
   resolved "https://registry.yarnpkg.com/@types/loader-utils/-/loader-utils-2.0.2.tgz#2999dc2a3330b3ac0b2eaa9e01328b3484ef1112"
@@ -10103,10 +10108,10 @@ hast-util-from-parse5@^6.0.0:
     vfile "^4.0.0"
     web-namespaces "^1.0.0"
 
-hast-util-is-element@^1.0.0:
+hast-util-is-element@1.1.0, hast-util-is-element@^1.0.0:
-  version "1.0.4"
+  version "1.1.0"
-  resolved "https://registry.yarnpkg.com/hast-util-is-element/-/hast-util-is-element-1.0.4.tgz#059090a05cc02e275df1ad02caf8cb422fcd2e02"
+  resolved "https://registry.yarnpkg.com/hast-util-is-element/-/hast-util-is-element-1.1.0.tgz#3b3ed5159a2707c6137b48637fbfe068e175a425"
-  integrity sha512-NFR6ljJRvDcyPP5SbV7MyPBgF47X3BsskLnmw1U34yL+X6YC0MoBx9EyMg8Jtx4FzGH95jw8+c1VPLHaRA0wDQ==
+  integrity sha512-oUmNua0bFbdrD/ELDSSEadRVtWZOf3iF6Lbv81naqsIV99RnSCieTbWuWCY8BAeEfKJTKl0gRdokv+dELutHGQ==
 
 hast-util-parse-selector@^2.0.0:
   version "2.2.3"
@@ -10145,7 +10150,7 @@ hast-util-to-string@^1.0.4:
   resolved "https://registry.yarnpkg.com/hast-util-to-string/-/hast-util-to-string-1.0.4.tgz#9b24c114866bdb9478927d7e9c36a485ac728378"
   integrity sha512-eK0MxRX47AV2eZ+Lyr18DCpQgodvaS3fAQO2+b9Two9F5HEoRPhiUMNzoXArMJfZi2yieFzUBMRl3HNJ3Jus3w==
 
-hast-util-to-text@^2.0.1:
+hast-util-to-text@^2.0.0, hast-util-to-text@^2.0.1:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/hast-util-to-text/-/hast-util-to-text-2.0.1.tgz#04f2e065642a0edb08341976084aa217624a0f8b"
   integrity sha512-8nsgCARfs6VkwH2jJU9b8LNTuR4700na+0h3PqCaEk4MAnMDeu5P0tP8mjk9LLNGxIeQRLbiDbZVw6rku+pYsQ==
@@ -12066,6 +12071,13 @@ jwt-decode@^2.2.0:
   resolved "https://registry.yarnpkg.com/jwt-decode/-/jwt-decode-2.2.0.tgz#7d86bd56679f58ce6a84704a657dd392bba81a79"
   integrity sha1-fYa9VmefWM5qhHBKZX3TkruoGnk=
 
+katex@^0.12.0:
+  version "0.12.0"
+  resolved "https://registry.yarnpkg.com/katex/-/katex-0.12.0.tgz#2fb1c665dbd2b043edcf8a1f5c555f46beaa0cb9"
+  integrity sha512-y+8btoc/CK70XqcHqjxiGWBOeIL8upbS0peTPXTvgrh21n1RiWWcIpSWM+4uXq+IAgNh9YYQWdc7LVDPDAEEAg==
+  dependencies:
+    commander "^2.19.0"
+
 kebab-case@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/kebab-case/-/kebab-case-1.0.0.tgz#3f9e4990adcad0c686c0e701f7645868f75f91eb"
@@ -16786,6 +16798,18 @@ regjsparser@^0.6.4:
   dependencies:
     jsesc "~0.5.0"
 
+rehype-katex@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/rehype-katex/-/rehype-katex-4.0.0.tgz#ce11a5db0bff014350e7a9cfd30147d314b14330"
+  integrity sha512-0mgBqYugQyIW0eUl6RDOZ28Cat2YzrnWGaYgKCMQnJw6ClmKgLqXBnkDAPGh2mwxvkkKwQOUMUpSLpA5rt7rzA==
+  dependencies:
+    "@types/katex" "^0.11.0"
+    hast-util-to-text "^2.0.0"
+    katex "^0.12.0"
+    rehype-parse "^7.0.0"
+    unified "^9.0.0"
+    unist-util-visit "^2.0.0"
+
 rehype-parse@^6.0.2:
   version "6.0.2"
   resolved "https://registry.yarnpkg.com/rehype-parse/-/rehype-parse-6.0.2.tgz#aeb3fdd68085f9f796f1d3137ae2b85a98406964"
@@ -16795,7 +16819,7 @@ rehype-parse@^6.0.2:
     parse5 "^5.0.0"
     xtend "^4.0.0"
 
-rehype-parse@^7.0.1:
+rehype-parse@^7.0.0, rehype-parse@^7.0.1:
   version "7.0.1"
   resolved "https://registry.yarnpkg.com/rehype-parse/-/rehype-parse-7.0.1.tgz#58900f6702b56767814afc2a9efa2d42b1c90c57"
   integrity sha512-fOiR9a9xH+Le19i4fGzIEowAbwG7idy2Jzs4mOrFWBSJ0sNUgy0ev871dwWnbOo371SjgjG4pwzrbgSVrKxecw==
@@ -16831,6 +16855,11 @@ remark-footnotes@2.0.0:
   resolved "https://registry.yarnpkg.com/remark-footnotes/-/remark-footnotes-2.0.0.tgz#9001c4c2ffebba55695d2dd80ffb8b82f7e6303f"
   integrity sha512-3Clt8ZMH75Ayjp9q4CorNeyjwIxHFcTkaektplKGl2A1jNGEUey8cKL0ZC5vJwfcD5GFGsNLImLG/NGzWIzoMQ==
 
+remark-math@^3.0.1:
+  version "3.0.1"
+  resolved "https://registry.yarnpkg.com/remark-math/-/remark-math-3.0.1.tgz#85a02a15b15cad34b89a27244d4887b3a95185bb"
+  integrity sha512-epT77R/HK0x7NqrWHdSV75uNLwn8g9qTyMqCRCDujL0vj/6T6+yhdrR7mjELWtkse+Fw02kijAaBuVcHBor1+Q==
+
 remark-mdx@1.6.22, remark-mdx@^1.6.21:
   version "1.6.22"
   resolved "https://registry.yarnpkg.com/remark-mdx/-/remark-mdx-1.6.22.tgz#06a8dab07dcfdd57f3373af7f86bd0e992108bbd"