Module system 

System preferences the UI follows (light / dark, accent colour, reduced motion, more contrast) and hand-offs to the OS (open a URL in the browser, open a file in its default app, reveal a file in the file manager).

Preferences are read on demand and cheap enough for a settings change or window focus, not for every frame: cache them and re-read when the window gains focus.

Structs

Preferences

What the user chose in the OS. None = unknown here.

Enums

Appearance

Constants

MAX_LANGUAGES

The most languages preferred_languages returns.

OPEN_URL_SCHEMES

URL schemes open_url hands to the OS. Anything else (file:, javascript:, custom app schemes) could start arbitrary programs, so it is refused.

Functions

bring_to_front

Bring the app and window to the front and give it the keyboard focus, restoring it if it is minimized. For “the second launch hands over to the first” and tray / global-shortcut activations, where the windowing library’s focus request alone may be refused.

check_url

Check a URL for open_url: an allowed scheme, one line, bounded.

open_path

Open a file or folder in its default app.

open_url

Open a web or mail link in the user’s default app.

preferences

The OS preferences now.

preferred_languages

The user’s preferred UI languages, most preferred first, as BCP 47 tags (en-GB, de, zh-Hans-CN): macOS NSLocale.preferredLanguages, Windows GetUserPreferredUILanguages; empty elsewhere (Linux has LANG/LANGUAGE) and when unknown. Desktop launches often have no LANG, so apps read this as well. At most MAX_LANGUAGES tags of at most 64 bytes.

reveal

Show a file selected in Finder / Explorer / the file manager.