Language Matching System

Attention 💥

Support since v0.2.17.

The language detection system is used for include app to provide accurate syntax highlighting based on file paths.

Overview

The language detection system intelligently identifies programming languages from file paths using a sophisticated three-tier matching system with clear precedence rules:

Priority	Method	Example	Description
1st (Highest)	Exact filename	`Dockerfile` → `dockerfile`	Perfect filename matches
2nd	File extension	`script.js` → `javascript`	Extension-based detection
3rd (Lowest)	Wildcard pattern	`Dockerfile.prod` → `dockerfile`	Flexible pattern matching

Configuration System

Configuration Location

Language definitions are stored in src/assets/config/languages.yaml. Each language entry supports multiple matching strategies.

You can override or extend the language detection rules in your book.toml. This is useful when you want to add support for new file extensions or modify existing detection rules without waiting for a new release.

Example book.toml configuration:

[preprocessor.embedify]
# Add .dockerfile extension to dockerfile language
include.languages.dockerfile.extensions = [".dockerfile"]
# Add specific filenames to dockerfile language(Optional)
include.languages.dockerfile.filenames = ["Dockerfile", "*.dockerfile"]

# Add a completely new language
include.languages.mylang.extensions = [".mlg"]
include.languages.mylang.filenames = ["MyLangFile", "MyLangFile.*"]

Language Definition Structure

- name: "dockerfile"
  extensions:
    - ".dockerfile"
  filenames:
    - "Dockerfile"
    - "dockerfile"
    - "Containerfile"
    - "Dockerfile.*"
    - "dockerfile.*"
    - "*.dockerfile"

Property	Type	Purpose	Example
`name`	String	Language identifier for syntax highlighting	`"javascript"`
`extensions`	Array	File extensions (with dots)	`[".js", ".jsx"]`
`filenames`	Array	Exact filenames and wildcard patterns	`["Dockerfile", "Makefile.", ".config.js"]`

Wildcard Pattern Syntax

Supported Wildcards

Wildcard	Regex	Description	Example Pattern	Matches
`*`	`.*`	Zero or more characters	`Dockerfile.*`	`Dockerfile.base`, `Dockerfile.production`
`?`	`.`	Exactly one character	`test?.txt`	`test1.txt`, `testa.txt`

Examples

🐳 Dockerfile Variants

Filename	Result	Reason
`Dockerfile`	`dockerfile`	✅ Exact match (non-wildcard entry)
`Dockerfile.base`	`dockerfile`	🔍 Pattern: `Dockerfile.*` (wildcard entry)
`Dockerfile.production`	`dockerfile`	🔍 Pattern: `Dockerfile.*` (wildcard entry)
`dockerfile.dev`	`dockerfile`	🔍 Pattern: `dockerfile.*` (wildcard entry)
`web.dockerfile`	`dockerfile`	🔍 Pattern: `*.dockerfile` (wildcard entry)
`api.dockerfile`	`dockerfile`	🔍 Pattern: `*.dockerfile` (wildcard entry)
`Dockerfile.js`	`javascript`	📁 Extension: `.js` (overrides pattern)

🔨 Makefile Variants

Filename	Result	Reason
`Makefile`	`makefile`	✅ Exact match (non-wildcard entry)
`Makefile.local`	`makefile`	🔍 Pattern: `Makefile.*` (wildcard entry)
`Makefile.am`	`makefile`	✅ Exact match (non-wildcard entry)
`custom.makefile`	`makefile`	📁 Extension: `.makefile`
`build.mk`	`makefile`	📁 Extension: `.mk`

🐚 Shell Configuration Files

Filename	Result	Reason
`.bashrc`	`shell`	✅ Exact match (non-wildcard entry)
`.zshrc`	`shell`	✅ Exact match (non-wildcard entry)
`custom.bashrc`	`shell`	🔍 Pattern: `*.bashrc` (wildcard entry)
`my.profile`	`shell`	🔍 Pattern: `*.profile` (wildcard entry)
`script.sh`	`shell`	📁 Extension: `.sh`

📦 Configuration Files

Filename	Result	Reason
`package.json`	`json`	📁 Extension: `.json`
`tsconfig.json`	`json`	📁 Extension: `.json`
`webpack.config.js`	`javascript`	📁 Extension: `.js`
`.eslintrc.json`	`json`	📁 Extension: `.json`

mdbook-embedify