refractor

Lightweight, robust, elegant virtual syntax highlighting using Prism. Useful for virtual DOMs and non-HTML things. Perfect for React, VDOM, and others.

refractor is built to work with all syntaxes supported by Prism, that’s 234 languages (as of prism@1.22.0) and all themes.

Want to use highlight.js instead? Try lowlight!

Contents

• Install
• Use
• API
  • refractor.register(syntax)
  • refractor.alias(name[, alias])
  • refractor.highlight(value, language)
  • refractor.registered(language)
  • refractor.listLanguages()
• Browser
• Plugins
• Syntaxes
• Related
• Projects

Install

npm:

npm install refractor

Use in the browser »

Use

var refractor = require('refractor')

var nodes = refractor.highlight('"use strict";', 'js')

console.log(nodes)

Yields:

[
  {
    type: 'element',
    tagName: 'span',
    properties: {className: ['token', 'string']},
    children: [{type: 'text', value: '"use strict"'}]
  },
  {
    type: 'element',
    tagName: 'span',
    properties: {className: ['token', 'punctuation']},
    children: [{type: 'text', value: ';'}]
  }
]

Which serialized with rehype or hast-util-to-html yields (you may have to wrap it into a fragment like so: {type: 'root', children: nodes}):

<span class="token string">"use strict"</span><span class="token punctuation">;</span>

Tip: Use hast-to-hyperscript to transform to other virtual DOMs, or DIY.

API

refractor.register(syntax)

Register a syntax. Needed if you’re using refractor/core.

Example

var refractor = require('refractor/core')
var markdown = require('refractor/lang/markdown')

refractor.register(markdown)

console.log(refractor.highlight('*Emphasis*', 'markdown'))

Yields:

[
  {
    type: 'element',
    tagName: 'span',
    properties: {className: [Array]},
    children: [[Object], [Object], [Object]]
  }
]

refractor.alias(name[, alias])

Register a new alias for the name language.

Signatures

• alias(name, alias|list)
• alias(aliases)

Parameters

• name (string) — Name of a registered language
• alias (string) — New alias for the registered language
• list (Array.<alias>) — List of aliases
• aliases (Object.<alias|list>) — Map where each key is a name and each value an alias or a list

Example

var refractor = require('refractor/core')
var markdown = require('refractor/lang/markdown')

refractor.register(markdown)

// refractor.highlight('*Emphasis*', 'mdown')
// ^ would throw: Error: Unknown language: `mdown` is not registered

refractor.alias({markdown: ['mdown', 'mkdn', 'mdwn', 'ron']})
refractor.highlight('*Emphasis*', 'mdown')
// ^ Works!

refractor.highlight(value, language)

Parse value (string) according to the language (name or alias) syntax.

Returns

Virtual nodes representing the highlighted value (Array.<Node>).

Example

var refractor = require('refractor/core')

console.log(refractor.highlight('em { color: red }', 'css'))

Yields:

[
  {
    type: 'element',
    tagName: 'span',
    properties: {className: [Array]},
    children: [[Object]]
  },
  {type: 'text', value: ' '},
  // …
  {type: 'text', value: ' red '},
  {
    type: 'element',
    tagName: 'span',
    properties: {className: [Array]},
    children: [[Object]]
  }
]

refractor.registered(language)

Check if a language (name or alias) is registered.

Example

var refractor = require('refractor/core')
var markdown = require('refractor/lang/markdown')

console.log(refractor.registered('markdown'))

refractor.register(markdown)

console.log(refractor.registered('markdown'))

Yields:

false
true

refractor.listLanguages()

List all registered languages (names and aliases).

Returns

Array.<string>.

Example

var refractor = require('refractor/core')
var markdown = require('refractor/lang/markdown')

console.log(refractor.listLanguages())

refractor.register(markdown)

console.log(refractor.listLanguages())

Yields:

[
  'markup',
  'html',
  // …
  'javascript',
  'js'
]
[
  'markup',
  'html',
  // …
  'javascript',
  'js',
  'markdown',
  'md'
]

Browser

I do not suggest using the pre-bundled files or requiring refractor itself in the browser as that would include a 376kb (139kb GZipped) of code.

Instead require refractor/core and include only the needed syntaxes. For example:

var refractor = require('refractor/core')

refractor.register(require('refractor/lang/jsx'))

console.log(refractor.highlight('<Dropdown primary />', 'jsx'))

Yields:

[
  {
    type: 'element',
    tagName: 'span',
    properties: {className: ['token', 'tag']},
    children: [
      {type: 'element', tagName: 'span', properties: {className: [Array]}, children: [[Object], [Object]]},
      {type: 'text', value: ' '},
      {type: 'element', tagName: 'span', properties: {className: [Array]}, children: [[Object]]},
      {type: 'text', value: ' '},
      {type: 'element', tagName: 'span', properties: {className: [Array]}, children: [[Object]]}
    ]
  }
]

…When using browserify and minifying with tinyify this results in just 65kb of code (23kb with GZip).

Plugins

refractor does not support Prism plugins:

1. Prism plugins often deal with the DOM, not Prism tokens
2. Prism is made using global variables instead of a module format, so all syntaxes below are custom built to work so you can require just what you need

Syntaxes

All syntaxes are included if you require('refractor'). If you’re using refractor/core, checked syntaxes are always included, but unchecked syntaxes are not and must be required and registered.

Unlike in Prism, cssExtras and phpExtras are camel-cased instead of dash-cased.

Only these custom built syntaxes will work with refractor because Prism’s own syntaxes are made to work with global variables and are not requirable.

• clike
• css
• javascript — alias: js
• markup — alias: html, mathml, svg, xml, ssml, atom, rss
• abap
• abnf
• actionscript
• ada
• agda
• al
• antlr4 — alias: g4
• apacheconf
• apl
• applescript
• aql
• arduino
• arff
• asciidoc — alias: adoc
• asm6502
• aspnet
• autohotkey
• autoit
• bash — alias: shell
• basic
• batch
• bbcode — alias: shortcode
• birb
• bison
• bnf — alias: rbnf
• brainfuck
• brightscript
• bro
• bsl
• c
• cil
• clojure
• cmake
• coffeescript — alias: coffee
• concurnas — alias: conc
• cpp
• crystal
• csharp — alias: dotnet, cs
• csp
• cssExtras
• cypher
• d
• dart
• dax
• dhall
• diff
• django — alias: jinja2
• dnsZoneFile
• docker — alias: dockerfile
• ebnf
• editorconfig
• eiffel
• ejs — alias: eta
• elixir
• elm
• erb
• erlang
• etlua
• excelFormula
• factor
• firestoreSecurityRules
• flow
• fortran
• fsharp
• ftl
• gcode
• gdscript
• gedcom
• gherkin
• git
• glsl
• gml
• go
• graphql
• groovy
• haml
• handlebars
• haskell — alias: hs
• haxe
• hcl
• hlsl
• hpkp
• hsts
• http
• ichigojam
• icon
• iecst
• ignore
• inform7
• ini
• io
• j
• java
• javadoc
• javadoclike
• javastacktrace
• jolie
• jq
• jsExtras
• jsTemplates
• jsdoc
• json — alias: webmanifest
• json5
• jsonp
• jsstacktrace
• jsx
• julia
• keyman
• kotlin — alias: kt, kts
• latex — alias: tex, context
• latte
• less
• lilypond
• liquid
• lisp
• livescript
• llvm
• lolcode
• lua
• makefile
• markdown — alias: md
• markupTemplating
• matlab
• mel
• mizar
• mongodb
• monkey
• moonscript — alias: moon
• n1ql
• n4js
• nand2tetrisHdl
• naniscript
• nasm
• neon
• nginx
• nim
• nix
• nsis
• objectivec — alias: objc
• ocaml
• opencl
• oz
• parigp
• parser
• pascal — alias: objectpascal
• pascaligo
• pcaxis — alias: px
• peoplecode — alias: pcode
• perl
• phpExtras
• php
• phpdoc
• plsql
• powerquery
• powershell
• processing
• prolog
• properties
• protobuf
• pug
• puppet
• pure
• purebasic
• purescript — alias: purs
• python — alias: py
• q
• qml
• qore
• r
• racket — alias: rkt
• reason
• regex
• renpy — alias: rpy
• rest
• rip
• roboconf
• robotframework
• ruby — alias: rb
• rust
• sas
• sass
• scala
• scheme
• scss
• shellSession
• smali
• smalltalk
• smarty
• sml — alias: smlnj
• solidity — alias: sol
• solutionFile
• soy
• sparql — alias: rq
• splunkSpl
• sqf
• sql
• stan
• stylus
• swift
• t4Cs
• t4Templating
• t4Vb
• tap
• tcl
• textile
• toml
• tsx
• tt2
• turtle
• twig
• typescript — alias: ts
• typoscript — alias: tsconfig
• unrealscript — alias: uc, uscript
• vala
• vbnet
• velocity
• verilog
• vhdl
• vim
• visualBasic
• warpscript
• wasm
• wiki
• xeora — alias: xeoracube
• xmlDoc
• xojo
• xquery
• yaml — alias: yml
• yang
• zig

Related

• lowlight — Same, but based on highlight.js

Projects

• react-syntax-highlighter — React component for syntax highlighting
• rehype-prism — Syntax highlighting in rehype
• react-refractor — Syntax highlighter for React

License

MIT © Titus Wormer