Cannot apply prettier because of `\`

[Nicolas Gaborit]

Sometimes, text containing '' are making prettier fail:

  1) slate-hyperprint text-escaping:
     SyntaxError: Unterminated string constant (13:32)
  11 |         </paragraph>
  12 |         <paragraph>
> 13 |             {'Should escape \\''}
     |                                ^
  14 |         </paragraph>
  15 |         <paragraph>
  16 |             {' '}
      at createError$1 (node_modules/prettier/parser-babylon.js:1:50)
      at parse (node_modules/prettier/parser-babylon.js:1:721)
      at Object.parse (node_modules/prettier/index.js:3763:12)
      at formatWithCursor (node_modules/prettier/index.js:21470:22)
      at format (node_modules/prettier/index.js:21510:10)
      at Object.format (node_modules/prettier/index.js:21735:12)
      at hyperprint (src/index.js:36:32)
      at Context.<anonymous> (tests/all.js:24:28)

[Nicolas Gaborit]

   SyntaxError: Expecting Unicode escape sequence \uXXXX (2:27)
      1 | <document>
    > 2 |     <x-embed data="{\"url\":\"https://some-url.com\",\"type\":\"some-type\",\"embed\":{\"type\":\"some-type\",\"url\":\"https://some-url.com\",\"html\":\"<div>some html</div>\"}}" />
        |                           ^
      3 | </document>

Here is another example that can't be prettied.