@theme-ui/prism

A syntax highlighting component based on
prism-react-renderer
that works seamlessly with Theme UI.

Installation

``
npm i @theme-ui/prism
`

Usage

The syntax highlighting component needs to be passed to Theme UI context via the
ThemeProvider.

`js
// src/components/layout.js
import { ThemeUIProvider } from 'theme-ui'
import { MDXProvider } from '@mdx-js/react'
import { useThemedStylesWithMdx } from '@theme-ui/mdx'
import Prism from '@theme-ui/prism'

import theme from './theme'

const components = {
pre: ({ children }) => <>{children},
code: Prism,
}

function Provider({ children }) {
const componentsWithStyles = useThemedStylesWithMdx(
useMDXComponents(components)
)

return (

{children}

)
}

export default Provider
`

Then, all code blocks in MDX documents wrapped by Layout will be syntax
highlighted.

$3

When using gatsby-plugin-theme-ui, shadow the
src/gatsby-plugin-theme-ui/components.js module to add the Prism component to
MDX scope.

`js
// src/gatsby-plugin-theme-ui/components.js
import Prism from '@theme-ui/prism'

export default {
pre: (props) => props.children,
code: Prism,
}
`

Syntax themes

This package includes the default syntax color themes from the prismjs and
prism-react-renderer packages. To add these to your Theme UI theme object,
import a preset and add the styles to theme.styles.code.

`js
// theme.js
import nightOwl from '@theme-ui/prism/presets/night-owl.json'

const theme = {
// ...theme
styles: {
code: {
...nightOwl,
},
},
}
`

The following themes are available and can be found in the
presets/
directory.

- dracula.json
- duotone-dark.json
- duotone-light.json
- github.json
- night-owl-light.json
- night-owl.json
- oceanic-next.json
- prism-coy.json
- prism-dark.json
- prism-funky.json
- prism-okaidia.json
- prism-solarizedlight.json
- prism-tomorrow.json
- prism-twilight.json
- prism.json
- shades-of-purple.json
- ultramin.json
- vs-dark.json

$3

To theme the prism styles based on the colors defined in your theme.colors
object, use the theme-ui preset, which will use the following color keys for
syntax highlight.

- gray
- primary
- secondary
- accent

`js
// src/gatsby-plugin-theme-ui/index.js
import prism from '@theme-ui/prism/presets/theme-ui'

export default {
colors: {
text: '#000',
background: '#fff',
primary: '#33e',
secondary: '#119',
accent: '#639',
gray: '#666',
},
styles: {
code: {
...prism,
},
},
}
`

Highlight support

This package supports highlighting inside code blocks. The following two
syntaxes are supported:

Single-line highlight by placing // highlight-line at the end of the line.

`js
let singleLineHighlight = 'there is a // highlight-line comment here ->' // highlight-line
`

Multi-line highlights by wrapping lines with // highlight-start and
// highlight-end. Multiple highlight wrappers are supported in a single code
block.

`js
// highlight-start
let multiLineHighlight =
this multiline string is wrapped by
// highlight-start and // highlight-end
comments

// highlight-end
`

The highlight styling is controlled in styles.pre under .highlight. For
example:

`json
".highlight": {
"background": "hsla(0, 0%, 30%, .5)"
}
`

Additional languages

Please note that @theme-ui/prism uses
prism-react-renderer,
which does not include all languages supported in Prism
by default. So, if you happen to use one of the missing languages, your code
block simply won't show up as highlighted.

For example, to add support for the R language, import the language and pass a
custom Prism instance to the Theme UI component:

`js
// src/gatsby-plugin-theme-ui/components.js
import ThemeUIPrism from '@theme-ui/prism'
import PrismCore from 'prismjs/components/prism-core'
import 'prismjs/components/prism-r'

export default {
pre: (props) => props.children,
code: (props) => ,
}
``