Update docs

doc/getting-started.md

@@ -83,13 +83,15 @@ npm install rehype
 `index.js` contains:
 
 ```js
-var rehype = require('rehype')
-var report = require('vfile-reporter')
-
-rehype().process('<title>Hi</title><h2>Hello world!', function(err, file) {
-  console.log(String(file))
-  console.log(report(err || file))
-})
+import {reporter} from 'vfile-reporter'
+import {rehype} from 'rehype'
+
+rehype()
+  .process('<title>Hi</title><h2>Hello world!')
+  .then((file) => {
+    console.log(String(file))
+    console.log(reporter(file))
+  })
 ```
 
 `node index.js` yields:

packages/rehype-parse/readme.md

@@ -66,6 +66,9 @@ Support this effort and give back by sponsoring on [OpenCollective][collective]!
 
 ## Install
 
+This package is [ESM only](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c):
+Node 12+ is needed to use it and it must be `import`ed instead of `require`d.
+
 [npm][]:
 
 ```sh
@@ -90,19 +93,22 @@ Say we have the following file, `example.html`, with a few errors:
 …and our script, `example.js`, looks as follows:
 
 ```js
-var vfile = require('to-vfile')
-var report = require('vfile-reporter')
-var unified = require('unified')
-var parse = require('rehype-parse')
-var rehype2remark = require('rehype-remark')
-var stringify = require('remark-stringify')
+import {readSync} from 'to-vfile'
+import {reporter} from 'vfile-reporter'
+import {unified} from 'unified'
+import rehypeParse from 'rehype-parse'
+import rehypeRemark from 'rehype-remark'
+import remarkStringify from 'remark-stringify'
+
+const file = readSync('example.html')
 
 unified()
-  .use(parse, {emitParseErrors: true, duplicateAttribute: false})
-  .use(rehype2remark)
-  .use(stringify)
-  .process(vfile.readSync('example.html'), function(err, file) {
-    console.error(report(err || file))
+  .use(rehypeParse, {emitParseErrors: true, duplicateAttribute: false})
+  .use(rehypeRemark)
+  .use(remarkStringify)
+  .process(file)
+  .then((file) => {
+    console.error(reporter(file))
     console.log(String(file))
   })
 ```
@@ -123,7 +129,10 @@ example.html
 
 ## API
 
-### `processor.use(parse[, options])`
+This package exports no identifiers.
+The default export is `rehypeParse`.
+
+### `unified().use(rehypeParse[, options])`
 
 Configure `processor` to parse HTML and create a [**hast**][hast] syntax tree.
 

packages/rehype-stringify/readme.md

@@ -66,6 +66,9 @@ Support this effort and give back by sponsoring on [OpenCollective][collective]!
 
 ## Install
 
+This package is [ESM only](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c):
+Node 12+ is needed to use it and it must be `import`ed instead of `require`d.
+
 [npm][]:
 
 ```sh
@@ -75,26 +78,29 @@ npm install rehype-stringify
 ## Use
 
 ```js
-var unified = require('unified')
-var createStream = require('unified-stream')
-var parse = require('rehype-parse')
-var stringify = require('rehype-stringify')
-
-var processor = unified()
-  .use(parse)
-  .use(stringify, {
+import {unified} from 'unified'
+import {stream} from 'unified-stream'
+import rehypeParse from 'rehype-parse'
+import rehypeStringify from 'rehype-stringify'
+
+const processor = unified()
+  .use(rehypeParse)
+  .use(rehypeStringify, {
     quoteSmart: true,
     closeSelfClosing: true,
     omitOptionalTags: true,
     entities: {useShortestReferences: true}
   })
 
-process.stdin.pipe(createStream(processor)).pipe(process.stdout)
+process.stdin.pipe(stream(processor)).pipe(process.stdout)
 ```
 
 ## API
 
-### `processor.use(stringify[, options])`
+This package exports no identifiers.
+The default export is `rehypeStringify`.
+
+### `unified().use(rehypeStringify[, options])`
 
 Configure `processor` to serialize [**hast**][hast] syntax trees to HTML.
 

packages/rehype/readme.md

@@ -74,6 +74,9 @@ Support this effort and give back by sponsoring on [OpenCollective][collective]!
 
 ## Install
 
+This package is [ESM only](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c):
+Node 12+ is needed to use it and it must be `import`ed instead of `require`d.
+
 [npm][]:
 
 ```sh
@@ -83,13 +86,15 @@ npm install rehype
 ## Use
 
 ```js
-var rehype = require('rehype')
-var report = require('vfile-reporter')
-
-rehype().process('<title>Hi</title><h2>Hello world!', function(err, file) {
-  console.log(report(err || file))
-  console.log(String(file))
-})
+import {reporter} from 'vfile-reporter'
+import {rehype} from 'rehype'
+
+rehype()
+  .process('<title>Hi</title><h2>Hello world!')
+  .then((file) => {
+    console.log(reporter(file))
+    console.log(String(file))
+  })
 ```
 
 Yields: