e30ae8ed09
- App.tsx: full navigation (Auth stack + Main tabs with 5 screens) - Auth: LoginScreen, RegisterScreen, ForgotPasswordScreen - HomeScreen: dashboard with IoT metrics, weather widget, alerts, quick actions, sensors - MapScreen: interactive map with layer toggles (6 layers) - MarketplaceScreen: categories (6), products (5), search - ChatScreen: AI chat with quick prompts (4), bot responses - ProfileScreen: user info, stats, menu (9 items), logout - AlertsScreen: alert list with severity, acknowledge - SensorsScreen: sensor list with type filters (6 types), search - ZonesScreen: zone cards with stats - SettingsScreen: language picker (FR/EN/ES/DE), privacy, about - Stores: iotStore (sensors, zones, alerts), notificationStore, uiStore + i18n - Hooks: useSensors, useAlerts, useNotifications, useLocation - Components: Card, Button, LoadingSpinner, ErrorBoundary, Header - Services: iotService, notificationService (with axios API client) - Utils: formatters (temp, AQI, noise, dates), validators (email, password, IBAN) - Theme: colors.ts with full design system (Blue Ocean palette) - Ditto: fixed MongoDB connection, new JWT secrets, official gateway image
80 lines
1.7 KiB
Markdown
80 lines
1.7 KiB
Markdown
# once
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Only call a function once.
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## usage
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```javascript
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var once = require('once')
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function load (file, cb) {
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cb = once(cb)
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loader.load('file')
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loader.once('load', cb)
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loader.once('error', cb)
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}
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```
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Or add to the Function.prototype in a responsible way:
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```javascript
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// only has to be done once
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require('once').proto()
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function load (file, cb) {
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cb = cb.once()
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loader.load('file')
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loader.once('load', cb)
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loader.once('error', cb)
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}
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```
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Ironically, the prototype feature makes this module twice as
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complicated as necessary.
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To check whether you function has been called, use `fn.called`. Once the
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function is called for the first time the return value of the original
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function is saved in `fn.value` and subsequent calls will continue to
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return this value.
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```javascript
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var once = require('once')
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function load (cb) {
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cb = once(cb)
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var stream = createStream()
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stream.once('data', cb)
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stream.once('end', function () {
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if (!cb.called) cb(new Error('not found'))
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})
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}
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```
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## `once.strict(func)`
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Throw an error if the function is called twice.
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Some functions are expected to be called only once. Using `once` for them would
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potentially hide logical errors.
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In the example below, the `greet` function has to call the callback only once:
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```javascript
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function greet (name, cb) {
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// return is missing from the if statement
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// when no name is passed, the callback is called twice
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if (!name) cb('Hello anonymous')
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cb('Hello ' + name)
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}
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function log (msg) {
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console.log(msg)
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}
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// this will print 'Hello anonymous' but the logical error will be missed
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greet(null, once(msg))
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// once.strict will print 'Hello anonymous' and throw an error when the callback will be called the second time
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greet(null, once.strict(msg))
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```
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