Syntax Highlighting

Table of contents

  1. Overview
  2. Supported Languages
  3. Configuration
    1. Enable/Disable
  4. Language Features
    1. Ruby
    2. C
    3. Go
    4. Rust
    5. JavaScript
    6. TypeScript
    7. Markdown
    8. HTML
    9. CSS
  5. Theme Colors

Overview

Mui includes built-in syntax highlighting for 9 programming languages. Highlighting is automatic based on file extension.

Supported Languages

Language Extensions
Ruby .rb, .rake, .gemspec
C .c, .h, .y
Go .go
Rust .rs
JavaScript .js, .mjs, .cjs, .jsx
TypeScript .ts, .tsx, .mts, .cts
Markdown .md, .markdown
HTML .html, .htm, .xhtml
CSS .css, .scss, .sass

Configuration

Enable/Disable 

# ~/.muirc
Mui.set :syntax, true   # Enable (default)
Mui.set :syntax, false  # Disable

Language Features

Ruby

  • Keywords (def, class, module, if, end, etc.)
  • Strings (single, double, heredoc)
  • Comments (#, =begin/=end)
  • Numbers
  • Symbols (:symbol)
  • Constants (CONSTANT, ClassName)
  • Instance variables (@foo, @@bar)
  • Global variables ($stdout)
  • Method calls (.to_s, .each)

C

  • Keywords (int, char, struct, if, for, etc.)
  • Strings and character literals
  • Comments (//, /* */)
  • Numbers
  • Preprocessor directives (#include, #define)

Go

  • Keywords (func, package, import, go, defer, etc.)
  • Types (int, string, bool, etc.)
  • Constants (true, false, nil, iota)
  • Strings (regular and raw backtick strings)
  • Comments (//, /* */)

Rust

  • Keywords (fn, let, mut, impl, trait, etc.)
  • Macros (println!, vec!)
  • Lifetimes ('a, 'static)
  • Attributes (#[derive], #[cfg])
  • Doc comments (///, //!)
  • Raw strings (r#"..."#)

JavaScript

  • ES6+ keywords (const, let, async, await, class)
  • Template literals (`template ${expr}`)
  • Regex literals (/pattern/flags)
  • BigInt (123n)
  • Strings and comments

TypeScript

All JavaScript features plus:

  • Type keywords (interface, type, enum, declare, abstract)
  • Type annotations

Markdown

  • Headings (#, ##, etc.)
  • Emphasis (*italic*, **bold**)
  • Code blocks (fenced and indented)
  • Links ([text](url))
  • Lists (ordered and unordered)
  • Blockquotes (>)

HTML

  • Tags (<div>, </div>, <br/>)
  • Attributes (class="...", id="...")
  • Comments (<!-- -->)
  • DOCTYPE
  • Entities (&amp;, &lt;)

CSS

  • Selectors (.class, #id, :pseudo, ::pseudo-element)
  • Properties and values
  • Hex colors (#fff, #ffffff)
  • At-rules (@media, @import, @keyframes)
  • Functions (calc(), rgb(), var())

Theme Colors

Syntax colors are defined per theme. All 8 built-in themes include syntax highlighting colors:

  • mui (default)
  • solarized_dark
  • solarized_light
  • monokai
  • nord
  • gruvbox_dark
  • dracula
  • tokyo_night

Each theme defines colors for:

Element Description
syntax_keyword Language keywords
syntax_string String literals
syntax_comment Comments
syntax_number Numeric literals
syntax_type Types and classes
syntax_function Function names
syntax_function_definition Function definition names
syntax_variable Variables
syntax_constant Constants
syntax_operator Operators
diagnostic_error LSP diagnostic errors
diagnostic_warning LSP diagnostic warnings
diagnostic_info LSP diagnostic information
diagnostic_hint LSP diagnostic hints
floating_window Floating window background