Pros of formatjs

• More comprehensive ecosystem with additional tools and libraries
• Wider adoption and community support
• Better integration with popular frameworks like React

Cons of formatjs

• Steeper learning curve due to more complex API
• Heavier bundle size, especially when using all features
• Less flexible syntax for translations in some cases

Code Comparison

formatjs:

import { FormattedMessage } from 'react-intl';

<FormattedMessage
  id="welcome"
  defaultMessage="Welcome, {name}!"
  values={{ name: userName }}
/>

js-lingui:

import { Trans } from '@lingui/macro';

<Trans id="welcome" values={{ name: userName }}>
  Welcome, {userName}!
</Trans>

Summary

formatjs offers a more comprehensive solution with wider adoption, but comes with a steeper learning curve and larger bundle size. js-lingui provides a simpler API and more flexible syntax for translations, but has a smaller ecosystem. Both libraries offer similar core functionality for internationalization, with formatjs providing more advanced features and integrations, while js-lingui focuses on simplicity and performance.

Pros of i18next

• Broader ecosystem with numerous plugins and integrations
• Supports more complex pluralization rules and nesting
• Extensive documentation and community support

Cons of i18next

• Steeper learning curve due to more features and options
• Can be overkill for smaller projects with simpler localization needs
• Slightly more verbose syntax for basic translations

Code Comparison

i18next:

import i18next from 'i18next';

i18next.init({
  lng: 'en',
  resources: {
    en: {
      translation: {
        key: 'Hello, {{name}}!'
      }
    }
  }
});

i18next.t('key', { name: 'World' });

js-lingui:

import { t } from '@lingui/macro';

const message = t`Hello, ${name}!`;

Summary

i18next is a powerful and flexible internationalization library with a vast ecosystem, making it suitable for complex projects with diverse localization needs. However, this power comes at the cost of a steeper learning curve and potentially more verbose syntax for basic use cases. js-lingui, on the other hand, offers a simpler API and more streamlined syntax, which can be advantageous for smaller projects or teams prioritizing ease of use. The choice between the two largely depends on the specific requirements of your project and the level of complexity you're willing to manage in your internationalization setup.

Pros of Polyglot.js

• Lightweight and simple to use, with minimal setup required
• Supports pluralization and interpolation out of the box
• Can be used in both browser and Node.js environments

Cons of Polyglot.js

• Limited features compared to more comprehensive i18n solutions
• Lacks advanced formatting options and custom plural rules
• No built-in support for extracting messages from source code

Code Comparison

Polyglot.js:

import Polyglot from 'node-polyglot';

const polyglot = new Polyglot();
polyglot.extend({greeting: 'Hello, %{name}!'});
console.log(polyglot.t('greeting', {name: 'John'}));

js-lingui:

import { t } from '@lingui/macro';

const name = 'John';
console.log(t`Hello, ${name}!`);

js-lingui offers a more natural syntax for translations using template literals, while Polyglot.js uses a more traditional key-based approach. js-lingui also provides additional features like message extraction, compilation, and more advanced pluralization rules, making it a more comprehensive solution for larger projects with complex internationalization needs.

Pros of formatjs

• More comprehensive ecosystem with additional tools and libraries
• Wider adoption and community support
• Better integration with popular frameworks like React

Cons of formatjs

• Steeper learning curve due to more complex API
• Heavier bundle size, especially when using all features
• Less flexible syntax for translations in some cases

Code Comparison

formatjs:

import { FormattedMessage } from 'react-intl';

<FormattedMessage
  id="welcome"
  defaultMessage="Welcome, {name}!"
  values={{ name: userName }}
/>

js-lingui:

import { Trans } from '@lingui/macro';

<Trans id="welcome" values={{ name: userName }}>
  Welcome, {userName}!
</Trans>

Summary

formatjs offers a more comprehensive solution with wider adoption, but comes with a steeper learning curve and larger bundle size. js-lingui provides a simpler API and more flexible syntax for translations, but has a smaller ecosystem. Both libraries offer similar core functionality for internationalization, with formatjs providing more advanced features and integrations, while js-lingui focuses on simplicity and performance.

Pros of vue-i18n

• Specifically designed for Vue.js, offering seamless integration
• Supports pluralization and datetime localization out of the box
• Provides a component-based approach for localization

Cons of vue-i18n

• Limited to Vue.js ecosystem, not suitable for other frameworks
• Lacks advanced features like automatic plurals and gender-aware translations
• May require more manual setup for complex localization scenarios

Code Comparison

vue-i18n:

const i18n = new VueI18n({
  locale: 'en',
  messages: {
    en: { hello: 'Hello' },
    ja: { hello: 'こんにちは' }
  }
})

js-lingui:

import { i18n } from "@lingui/core";
import { en, ja } from "make-plural/plurals";

i18n.loadLocaleData({
  en: { plurals: en },
  ja: { plurals: ja }
});

Key Differences

• js-lingui is framework-agnostic, while vue-i18n is Vue-specific
• js-lingui offers more advanced features like automatic plurals and gender-aware translations
• vue-i18n provides easier integration with Vue components
• js-lingui uses a macro-based approach for translations, potentially reducing runtime overhead
• vue-i18n has built-in support for date and number formatting, while js-lingui requires additional setup

Both libraries are popular choices for internationalization, with the choice depending on the specific project requirements and framework preferences.

Pros of go-i18n

• Written in Go, offering better performance and concurrency support
• Supports plural forms and gender-specific translations
• Includes a command-line tool for managing translation files

Cons of go-i18n

• Limited framework integration compared to js-lingui
• Lacks advanced features like ICU MessageFormat support
• Primarily focused on Go applications, limiting its use in other environments

Code Comparison

js-lingui:

import { t } from "@lingui/macro";

const greeting = t`Hello, ${name}!`;

go-i18n:

import "github.com/nicksnyder/go-i18n/v2/i18n"

localizer := i18n.NewLocalizer(bundle, "en")
greeting := localizer.MustLocalize(&i18n.LocalizeConfig{
    DefaultMessage: &i18n.Message{
        ID:    "Greeting",
        Other: "Hello, {{.Name}}!",
    },
    TemplateData: map[string]string{"Name": name},
})

Key Differences

• js-lingui is designed for JavaScript/TypeScript projects, while go-i18n is tailored for Go applications
• js-lingui offers more extensive React integration and supports ICU MessageFormat
• go-i18n provides built-in pluralization and gender-specific translations
• js-lingui has a more streamlined syntax for basic translations
• go-i18n includes a command-line tool for managing translation files, which js-lingui lacks

Both libraries aim to simplify internationalization in their respective ecosystems, with js-lingui focusing on modern JavaScript frameworks and go-i18n catering to Go developers.