TypeScript命名空间-蒲公英云

namespace 命名空间，可以把一组全局变量封装成一个统一的接口，选择性的进行暴露，实现组件化开发思想。

用 namespace Home 包裹全局变量
需要暴露的变量使用 export 导出
使用 new Home.Page() 执行

// page.ts
///<reference path='./components.ts' />
namespace Home { 
  export class Page { 
    constructor() { 
      new Component.Header();
      new Component.Content();
      new Component.Footer();
    }
  }
}
// components.ts
namespace Component { 
  const common = (title: string): void => { 
    const elem = document.createElement('div');
    elem.innerHTML = `This is ${ title}`;
    document.body.appendChild(elem);
  };
  export class Header { 
    constructor() { 
      common('Header');
    }
  }
  export class Content { 
    constructor() { 
      common('Content');
    }
  }
  export class Footer { 
    constructor() { 
      common('Footer');
    }
  }
}
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <script src="./dist/page.js"></script>
  <script> new Home.Page(); </script>
</body>
</html>
// tsconfig.json
{ 
  "compilerOptions": { 
    /* Basic Options */
    // "incremental": true, /* Enable incremental compilation */
    "target": "es5",
    /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019', 'ES2020', or 'ESNEXT'. */
    "module": "amd",
    /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', 'es2020', or 'ESNext'. */
    // "lib": [], /* Specify library files to be included in the compilation. */
    // "allowJs": true, /* Allow javascript files to be compiled. */
    // "checkJs": true, /* Report errors in .js files. */
    // "jsx": "preserve", /* Specify JSX code generation: 'preserve', 'react-native', or 'react'. */
    // "declaration": true, /* Generates corresponding '.d.ts' file. */
    // "declarationMap": true, /* Generates a sourcemap for each corresponding '.d.ts' file. */
    // "sourceMap": true, /* Generates corresponding '.map' file. */
    "outFile": "./dist/page.js",
    /* Concatenate and emit output to single file. */
    "outDir": "./dist",
    /* Redirect output structure to the directory. */
    "rootDir": "./src",
    /* Specify the root directory of input files. Use to control the output directory structure with --outDir. */
    // "composite": true, /* Enable project compilation */
    // "tsBuildInfoFile": "./", /* Specify file to store incremental compilation information */
    // "removeComments": true, /* Do not emit comments to output. */
    // "noEmit": true, /* Do not emit outputs. */
    // "importHelpers": true, /* Import emit helpers from 'tslib'. */
    // "downlevelIteration": true, /* Provide full support for iterables in 'for-of', spread, and destructuring when targeting 'ES5' or 'ES3'. */
    // "isolatedModules": true, /* Transpile each file as a separate module (similar to 'ts.transpileModule'). */
    /* Strict Type-Checking Options */
    "strict": true,
    /* Enable all strict type-checking options. */
    // "noImplicitAny": true, /* Raise error on expressions and declarations with an implied 'any' type. */
    // "strictNullChecks": true, /* Enable strict null checks. */
    // "strictFunctionTypes": true, /* Enable strict checking of function types. */
    // "strictBindCallApply": true, /* Enable strict 'bind', 'call', and 'apply' methods on functions. */
    // "strictPropertyInitialization": true, /* Enable strict checking of property initialization in classes. */
    // "noImplicitThis": true, /* Raise error on 'this' expressions with an implied 'any' type. */
    // "alwaysStrict": true, /* Parse in strict mode and emit "use strict" for each source file. */
    /* Additional Checks */
    // "noUnusedLocals": true, /* Report errors on unused locals. */
    // "noUnusedParameters": true, /* Report errors on unused parameters. */
    // "noImplicitReturns": true, /* Report error when not all code paths in function return a value. */
    // "noFallthroughCasesInSwitch": true, /* Report errors for fallthrough cases in switch statement. */
    /* Module Resolution Options */
    // "moduleResolution": "node", /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */
    // "baseUrl": "./", /* Base directory to resolve non-absolute module names. */
    // "paths": {}, /* A series of entries which re-map imports to lookup locations relative to the 'baseUrl'. */
    // "rootDirs": [], /* List of root folders whose combined content represents the structure of the project at runtime. */
    // "typeRoots": [], /* List of folders to include type definitions from. */
    // "types": [], /* Type declaration files to be included in compilation. */
    // "allowSyntheticDefaultImports": true, /* Allow default imports from modules with no default export. This does not affect code emit, just typechecking. */
    "esModuleInterop": true,
    /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
    // "preserveSymlinks": true, /* Do not resolve the real path of symlinks. */
    // "allowUmdGlobalAccess": true, /* Allow accessing UMD globals from modules. */
    /* Source Map Options */
    // "sourceRoot": "", /* Specify the location where debugger should locate TypeScript files instead of source locations. */
    // "mapRoot": "", /* Specify the location where debugger should locate map files instead of generated locations. */
    // "inlineSourceMap": true, /* Emit a single file with source maps instead of having a separate file. */
    // "inlineSources": true, /* Emit the source alongside the sourcemaps within a single file; requires '--inlineSourceMap' or '--sourceMap' to be set. */
    /* Experimental Options */
    // "experimentalDecorators": true, /* Enables experimental support for ES7 decorators. */
    // "emitDecoratorMetadata": true, /* Enables experimental support for emitting type metadata for decorators. */
    /* Advanced Options */
    "forceConsistentCasingInFileNames": true /* Disallow inconsistently-cased references to the same file. */
  }
}