Custom syntaxes

Load definitions

--syntaxes-dir DIR recursively loads .sublime-syntax files on top of the embedded syntax set. Custom definitions take precedence over matching embedded syntaxes. A missing directory or invalid definition is an error, rather than a silent switch to plain text.

mdv --syntaxes-dir ./syntaxes README.md

Minimal example

Save this as syntaxes/Acme.sublime-syntax:

%YAML 1.2
---
name: Acme
file_extensions: [acme]
scope: source.acme
contexts:
  main:
    - match: '\b(let|print)\b'
      scope: keyword.control.acme

Use acme as the Markdown code fence’s language hint. Define icons, display names and additional aliases separately:

mdv --syntaxes-dir ./syntaxes --custom-code-block 'acme:label=Acme,icon=*,aliases=ac' README.md

Configuration paths and detection

syntaxes_dir saves the directory in YAML.

• Relative YAML paths start from the configuration directory; a CLI relative path is relative to the current working directory.
• Custom aliases affect lookup, while custom code labels alone do not add a grammar.
• --no-code-guessing disables heuristic detection without disabling explicit syntax selection.