Documentation: t Function in react-intlayer

The t function in the react-intlayer package is a fundamental tool for inline internationalisation within your React application. It allows you to define translations directly within your components, making it simple to display localised content based on the current locale.

Overview

The t function is used to provide translations for different locales directly in your components. By passing an object containing translations for each supported locale, t returns the appropriate translation based on the current locale context in your React application.

Key Features

• Inline Translations: Ideal for quick, inline text that doesn't require a separate content declaration.
• Automatic Locale Selection: Returns the translation corresponding to the current locale automatically.
• TypeScript Support: Provides type safety and autocompletion when used with TypeScript.
• Easy Integration: Works seamlessly within React components.

Function Signature

t<T extends string>(content: Record<LocalesValues, T>, locale?: Locales): string

Parameters

• translations: An object where keys are locale codes (e.g., en, fr, es) and values are the corresponding translated strings.

Returns

• A string representing the translated content for the current locale.

Usage Examples

Basic Usage of t in a Component

import type { FC } from "react";
import { t } from "react-intlayer";

export const ComponentExample: FC = () => {
  return (
    <div>
      <p>
        {t({
          en: "This is an example of a component",
          fr: "Ceci est un exemple de composant",
          es: "Este es un ejemplo de componente",
        })}
      </p>
    </div>
  );
};

Inline Translations in Attributes

The t function is especially useful for inline translations within JSX attributes. When localising attributes such as alt, title, href, or aria-label, you can use t directly inside the attribute.

<button
  aria-label={t({
    en: "Submit",
    fr: "Soumettre",
    es: "Enviar",
  })}
>
  {t({
    en: "Submit",
    fr: "Soumettre",
    es: "Enviar",
  })}
  <img
    src="/path/to/image"
    alt={t({
      en: "A beautiful scenery",
      fr: "Un beau paysage",
      es: "Un hermoso paisaje",
    })}
  />
</button>

Advanced Topics

TypeScript Integration

The t function is type-safe when used with TypeScript, ensuring that all required locales are provided.

import { t, type IConfigLocales } from "react-intlayer";

const translations: IConfigLocales<string> = {
  en: "Welcome",
  fr: "Bienvenue",
  es: "Bienvenido",
};

const greeting = t(translations);

Locale Detection and Context

In react-intlayer, the current locale is managed through the IntlayerProvider. Ensure this provider wraps your components and the locale prop is correctly passed.

Example:

import type { FC } from "react";
import type { Locales } from "intlayer";
import { IntlayerProvider } from "react-intlayer";

const App: FC<{ locale: Locales }> = ({ locale }) => (
  <IntlayerProvider locale={locale}>
    {/* Your components here */}
  </IntlayerProvider>
);

Common Errors and Troubleshooting

t Returns Undefined or Incorrect Translation

• Cause: The current locale is not properly set, or the translation for the current locale is missing.
• Solution:
  • Verify that the IntlayerProvider is correctly set up with the appropriate locale.
  • Ensure that your translations object includes all the necessary locales.

Missing Translations in TypeScript

• Cause: Translations object does not satisfy the required locales, leading to TypeScript errors.
• Solution: Use the IConfigLocales type to enforce completeness of your translations.

const translations: IConfigLocales<string> = {
  en: "Text",
  fr: "Texte",
  // es: 'Texto', // Missing 'es' will cause a TypeScript error
};

const text = t(translations);

Tips for Effective Usage

1. Use t for Simple Inline Translations: Ideal for translating small pieces of text directly within your components.
2. Prefer useIntlayer for Structured Content: For more complex translations and content reuse, define content in declaration files and use useIntlayer.
3. Consistent Locale Provision: Ensure that your locale is consistently provided across your application through the IntlayerProvider.
4. Leverage TypeScript: Use TypeScript types to catch missing translations and ensure type safety.

Conclusion

The t function in react-intlayer is a powerful and convenient tool for managing inline translations in your React applications. By integrating it effectively, you enhance the internationalisation capabilities of your app, providing a better experience for users worldwide.

For more detailed usage and advanced features, refer to the react-intlayer documentation.

Note: Remember to set up your IntlayerProvider properly to ensure that the current locale is correctly passed down to your components. This is crucial for the t function to return the correct translations.