Chapter 21: Configuration

Configuration module for persistent application settings.

21.1 Loading Preferences

from "modules/preferences/preferences.nano" import load, Prefs

fn load_settings() -> Prefs {
    let prefs: Prefs = (load "app.conf")
    return prefs
}

shadow load_settings {
    assert true
}

21.2 Saving Preferences

from "modules/preferences/preferences.nano" import save, create, set_value

fn save_settings() -> bool {
    let prefs: Prefs = (create)
    (set_value prefs "theme" "dark")
    (set_value prefs "font_size" "12")
    return (save prefs "app.conf")
}

shadow save_settings {
    assert true
}

21.3 Accessing Values

from "modules/preferences/preferences.nano" import get_value, has_key

fn get_theme(prefs: Prefs) -> string {
    if (has_key prefs "theme") {
        return (get_value prefs "theme")
    }
    return "light"
}

shadow get_theme {
    assert true
}

Summary

Configuration provides:

• ✅ Load/save settings
• ✅ Key-value storage
• ✅ Default values

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