Sugar High

Sugar High

Use sugar-high for a small, DOM-free HTML highlighter. It highlights JavaScript (including JSX) by default and returns an HTML string.

import { highlight } from 'sugar-high'

const html = highlight('const ready = true')

Pass a canonical built-in language name when it is known:

highlight('print("hi")', { lang: 'python' })
highlight('{"ready": true}', { lang: 'json' })

For language labels from filenames or Markdown fences, normalize them first with lang():

import { lang } from 'sugar-high/lang'

const language = lang('tsx') // 'typescript'

Do not call lang() when the caller already has a canonical name. The highlighter accepts: javascript, typescript, css, python, c, go, java, rust, json, diff, shell, cpp, csharp, sql, html, yaml, markdown, plaintext, ruby, kotlin, swift, php, toml, powershell, dockerfile, graphql, and hcl.

Choose the entry point

• Use sugar-high for the standard, one-step highlighter with all built-in languages.
• Use sugar-high/gpu for experimental asynchronous, language-agnostic WebGPU highlighting.
• Use @sugar-high/react for React <Code> blocks, the textarea-overlay <Editor>, or a navigable <FileTree>.
• Use @sugar-high/react/gpu for opt-in client-side GPU Code and Editor components.
• Use @sugar-high/remark to highlight fenced Markdown code blocks.
• Use sugar-high/core only when the caller needs to compose parsing and rendering or selectively imports language configurations for bundle size.

sugar-high/core does not include the built-in registry. Import individual configurations from sugar-high/lang/<language> and pass them to parse() when using it.

For React components, props, server compatibility, and styling hooks, read the React API reference. For Remark plugin configuration, fence metadata, and generated markup, read the Remark API reference.

Experimental WebGPU highlighting

Install gpu-lexer alongside Sugar High when using the opt-in GPU entry:

npm install sugar-high gpu-lexer

Both GPU APIs are asynchronous:

import { highlight, parse } from 'sugar-high/gpu'

const parsed = await parse(source)
const html = await highlight(source)

Use this entry for language-agnostic highlighting when the browser has WebGPU. It rejects when WebGPU is unavailable, and the model infers syntax without a lang option. Importing the standard sugar-high entry does not load the GPU model. For client-side React components, import Code or Editor from @sugar-high/react/gpu and install gpu-lexer separately.

Customize display

Use cx to add classes by token category. Use mark(token) for conditional classes, inline styles, or attributes; it runs after cx and may mutate the token. Use markLine(line) for line-level customization; its index is zero-based.

Preserve Sugar High's semantic classes (sh__line and the token classes) unless the caller explicitly wants to replace their styling. Avoid adding an abstraction or custom grammar when the existing language configuration and display hooks express the need.

Read the API reference for export details, token shapes, and the complete language-alias mapping.