what is the correct way to add type definition for this module

import statements are used for .ts files not for .d.ts files. For those you need to use the ///<reference .../> tags or simple import React = __React; type imports.

Here is what I could come up with using the react.d.ts file and the React Switch source code.

///<reference path="../react/react.d.ts"/>
declare module 'react-bootstrap-switch'
{
    function Switch(): __React.ClassicComponentClass;

    export  = Switch;
}

How you use typescript, and how you write definition files for JS libraries are two completely different things. If this does not work for you then I suppose I could pull down the repos and get it building.

Update

Ok I have a working version

declare module 'react-bootstrap-switch'{
    interface SwitchProps{
        onColor?: string
    }

    class Switch extends __React.Component<SwitchProps, {}>{}

    export = Switch;
}

Usage import Switch = require('react-bootstrap-switch');

And before you comment saying that you can't switch the import...

Please read the answer here explaining why. And please run the code. You will see that the JS version of the library still loads as expected and still runs.

I need to credit this post and this definition for their help in this.

My test file for compiling:

import * as React from 'react';
import Switch = require('react-bootstrap-switch');

var b = <div></div>;
var a = <Switch/>;

The resulting output:

var React = require('react');
var Switch = require('react-bootstrap-switch');
var b = React.createElement("div", null);
var a = React.createElement(Switch, null);

As you can see the output is identical for either import and the build is error free.

And tsconfig.js:

{
    "compilerOptions": {
        "module": "commonjs",
        "target": "es3",
        "noImplicitAny": false,
        "outDir": "built",
        "rootDir": ".",
        "sourceMap": false,
        "moduleResolution": "node",
        "jsx": "react"
    },
    "exclude": [
        "node_modules"
    ]
}