typescript - what is the purpose of tsconfig.json?

Question

I was reading angular2 referrences and found this tsconfig.json. I would like to know what the following parameters mean?

{
    "compilerOptions": {
        "target": "es5",
        "module": "system",
        "moduleResolution": "node",
        "sourceMap": true,
        "emitDecoratorMetadata": true,
        "experimentalDecorators": true,
        "removeComments": false,
        "noImplicitAny": false
    },
    "exclude": [
        "node_modules"
    ]
}

Answer 1

The tsconfig.json file corresponds to the configuration of the TypeScript compiler (tsc).

These links could give you details about these attributes:

• http://www.typescriptlang.org/docs/handbook/tsconfig-json.html
• http://json.schemastore.org/tsconfig
• https://angular.io/docs/ts/latest/guide/typescript-configuration.html#!#tsconfig

Here are some hints:

• target: the language used for the compiled output
• module: the module manager used in the compiled output. system is for SystemJS, commonjs for CommonJS.
• moduleResolution: the strategy used to resolve module declaration files (.d.ts files). With the node approach, they are loaded from the node_modules folder like a module (require('module-name'))
• sourceMap: generate or not source map files to debug directly your application TypeScript files in the browser,
• emitDecoratorMetadata: emit or not design-type metadata for decorated declarations in source,
• experimentalDecorators: enables or not experimental support for ES7 decorators,
• removeComments: remove comments or not
• noImplicitAny: allow or not the use of variables / parameters without types (implicit)