English | 中文

@1-/oslang : OS language detection utility

• @1-/oslang : OS language detection utility
  • Functionality
  • Usage demonstration
  • Design rationale
  • Technology stack
  • Code structure
  • Historical context
  • About

Functionality

Detects user's preferred language from operating system environment variables and browser/system locale settings, with normalization and hierarchical matching support. Implements multi-level fallback (e.g., zh-CN → zh) to reliably select the best-fit language in internationalized applications.

Usage demonstration

npm install @1-/oslang

import oslang from "@1-/oslang";
import match from "@1-/oslang/match.js";

// Get all normalized, deduplicated language tags, including parent languages
console.log([...oslang]); // ['en-US', 'en', 'zh-CN', 'zh']

// Match against a list of available languages
const available = ["en", "zh", "ja", "ko"];
const preferred = match(available).next().value;
console.log(preferred); // 'zh' (if system is zh-CN) or undefined (if no match)

Design rationale

The library uses a deterministic priority order: sources are tried sequentially, then results are normalized and expanded to include parent locales:

Technology stack

• Node.js runtime (ESM modules)
• Standard JavaScript (zero external dependencies)
• Intl.DateTimeFormat().resolvedOptions().locale API
• node:process.env for environment variable access

Code structure

src/
├── _.js        # Main export: yields raw language sources (env + Intl + fallback)
├── all.js      # Normalized set: deduplicated, lowercase, hyphen-separated, with auto-added parent languages (e.g., en-US → en)
├── match.js    # Matching function: returns iterator yielding first matched item (original input)
└── parse.js    # Normalization utility: strips encoding suffixes, replaces `_` with `-`, lowercases

Historical context

The POSIX standard, first published in 1988 (IEEE Std 1003.1-1988), formally standardized LC_* environment variables (e.g., LC_MESSAGES, LC_TIME) to provide portable localization on Unix systems. LANG served as the default fallback, while LANGUAGE was later extended by GNU to support ordered language preference lists (e.g., zh_CN:zh_TW). This library carries forward that four-decade tradition, re-implementing its core semantics in modern JavaScript.

About

This library is developed by WebC.site.

WebC.site: A new paradigm of web development for AI

@1-/oslang : 操作系统语言检测工具

• @1-/oslang : 操作系统语言检测工具
  • 功能介绍
  • 使用演示
  • 设计思路
  • 技术栈
  • 代码结构
  • 历史故事
  • 关于

功能介绍

从操作系统环境变量与浏览器/系统区域设置中检测用户首选语言，提供标准化处理与层级匹配能力。支持多级语言回退（如 zh-CN → zh），确保在国际化应用中可靠选择最适配的语言。

使用演示

npm install @1-/oslang

import oslang from "@1-/oslang";
import match from "@1-/oslang/match.js";

// 获取所有已标准化、去重且含父语言的语言标识符
console.log([...oslang]); // ['en-US', 'en', 'zh-CN', 'zh']

// 在可用语言列表中匹配最优项
const available = ["en", "zh", "ja", "ko"];
const preferred = match(available).next().value;
console.log(preferred); // 'zh'（若系统为 zh-CN）或 undefined（若无匹配）

设计思路

本库采用确定性优先级策略，按顺序尝试多种来源，并对结果进行标准化与层级扩展：

技术栈

• Node.js 运行时（ESM 模块）
• 标准 JavaScript（无外部依赖）
• Intl.DateTimeFormat().resolvedOptions().locale API
• node:process.env 环境读取

代码结构

src/
├── _.js        # 主导出：生成原始语言源（环境变量 + Intl + fallback）
├── all.js      # 标准化集：去重、小写、短横线分隔，并自动添加父语言（如 en-US → en）
├── match.js    # 匹配函数：返回迭代器，yield 首个匹配项（原始输入项）
└── parse.js    # 标准化工具：移除编码后缀、下划线转短横线、转小写

历史故事

POSIX 标准于 1988 年首次发布（IEEE Std 1003.1-1988），正式将 LC_* 环境变量（如 LC_MESSAGES, LC_TIME）纳入规范，为 Unix 系统提供可移植的本地化机制。LANG 变量作为默认兜底，LANGUAGE 则被 GNU 系统扩展用于多语言优先级列表（如 zh_CN:zh_TW）。本库延续这一四十年传统，在现代 JavaScript 环境中轻量复现其核心语义。

关于

本库由 WebC.site 开发。

WebC.site : 面向人工智能的网站开发新范式