Translations

The interface is in English (the default) and German, chosen under Settings → Language. Code, comments and this documentation are in English.

Where the texts live

Texts	Where	How
Interface labels, hints, panel texts	desktop/src/i18n/en.ts, de.ts	one object per language with the same keys
Menu	desktop/src-tauri/src/shell.rs	l("English", "Deutsch") in build_menu
Errors of the Tauri shell	desktop/src-tauri/src/commands.rs	the text! macro
Analysis and electronics working, notes and errors	next to their code in crates/quantus-core/src/analysis/ and electro/	the msg! macro of crate::text
Parser and algebra messages	crates/quantus-core/src/latex/, algebra/, eval/	English only

The renderer

en.ts defines the keys; de.ts must have exactly the same ones, which the type Record<TextKey, string> in desktop/src/i18n/index.tsx enforces at npm run typecheck. Placeholders are written {name} and filled by t(key, { name }):

'footer.counts': '{variables} variables · {history} history entries',

To add a text, add the key to en.ts, the translation to de.ts, and use t('your.key') in the component.

The engine

Engine texts are written with both languages side by side:

msg!("Unknown: {}", "Unbekannt: {}", reason.text())

msg! picks the language of the current call, which the API functions set with a Scope from the settings. Outside a call it is English.

Adding a language

1. Add the variant to Language in crates/quantus-core/src/settings.rs and to the Language type in desktop/src/api.ts.
2. Add a dictionary desktop/src/i18n/xx.ts and its native name to LANGUAGE_NAMES.
3. Extend msg!, text! and the menu's l with the new language. The compiler lists every place that needs a text.