The setting
I am trying to load existing AMD modules with TypeScript.
To demonstrate my problem, here is an app.ts file that loads an AMD module named my_amd_module.js:
// app.ts
import * as amd_func from './my_amd_module';
function main(): void {
console.log(amd_func());
}
main();
The following TypeScript configuration is used:
// tsconfig.json
{
"compileOnSave": true,
"compilerOptions": {
"allowJs": true,
"outDir": "build",
"sourceMap": true,
"target": "es5"
},
"exclude": [
"node_modules",
"build"
]
}
And I am using Webpack to bundle the app.ts file in a package named app-bundle.js that can be run by a browser:
// webpack.config.js
'use strict';
const webpack = require('webpack');
const path = require('path');
module.exports = {
context: path.resolve(__dirname, 'src'),
entry: './app.ts',
output: {
path: path.resolve(__dirname, 'build'),
filename: 'app-bundle.js'
},
devtool: 'source-map',
resolve: {
extensions: ['', '.ts', '.js']
},
module: {
loaders: [
{test: /\.ts$/, loader: 'ts-loader'}
]
}
};
The working version
When the my_amd_module.js looks as following, everything is working fine. Notice that I am referencing 'module' as a dependency and bind the function foo to it’s exports property which is one possible flavor of using AMD.
// my_amd_module.js
define(['module'], function(module) {
function foo () {
return 'Hello from AMD!';
}
module.exports = foo;
});
The not working version
But when I am using the alternative syntax of defining an AMD module with a return value instead of assigning to exports
// my_amd_module.js
define(function() {
function foo () {
return 'Hello from AMD!';
}
return foo;
});
then the TypeScript compiler complains with the following message:
ERROR in ./app.ts
(1,27): error TS2306: File '/[...]/src/my_amd_module.js' is not a module.
But the app-bundle.js file is still generated and everything works in the browser.
The alternative syntax I am using in this case is, for example, described by RequireJS or in the AMD specification itself.
My question
Are AMD modules that define their exported value with a return value instead of assigning to exports not supported by TypeScript? Is this the reason why the compiler is complaining? And why is everything compiled, despite this complaint?
