Declare node module for TypeScript that is not available within typings

Question

I'm quite new to TypeScript and am trying to script a little cli app.

I want to use npm~command-line-args but its definition is not available with typings so I thought how hard could it be to create my own. Turns out it is harder than I expected.

So my goal is to export a module which exposes just a single function and maybe a small type declaration.

I tried this so far:

declare module 'command-line-args' {
  export interface cliOptionDefinition {
    name: string,
    alias?: string,
    type: BooleanConstructor|StringConstructor|NumberConstructor,
    multiple?: Boolean,
    defaultOption?: any
  }

  export = function commandLineArgs <R> ( optionDefinitions: cliOptionDefinition[] ) {};
}

But am getting this error:
error TS1183: An implementation cannot be declared in ambient contexts.

Answer 1

Does:

export function commandLineArgs <R> ( optionDefinitions: cliOptionDefinition[] );

work the way that you would expect? (Omit the = , and the {} .) If you are intending to provide an implementation of commandLineArgs , then you want to export it from a non-ambient (remove declare etc.), preferably external, module (or, alternatively, namespace).

Answer 2

你应该看一下Polymer项目（例如polymer-cli ） - 他们使用带有Typescript的命令行参数。