Duplicate identifiers

[davidleureka]

I'm having an issue with duplicate identifier errors. It appears to stem from having the same definitions listed in multiple places.

Let's say that I have a simple node server that utilizes the bluebird promise library. I have bluebird used in the main server code and in a library I wrote used by the server code. The structure looks like this:

|-- server.ts
|-- tsd.json
|-- typings
|-- lib
    |-- mylib.ts
    |-- tsd.json
    |-- typings

Here is the code for and for mylib.ts:

/// <reference path="./typings/tsd.d.ts"/>
import Promise = require('bluebird')
class MyLib {
}
export = MyLib

and server.ts:

/// <reference path="./typings/tsd.d.ts"/>
import Promise = require('bluebird')
import MyLib = require('./lib/mylib')
class Server {
}
export = Server

As you can see, both server.ts and mylib.ts use the bluebird library. Since server.ts uses mylib.ts, it ends up importing bluebird twice, which results in errors. So when I run

tsc server.ts --module commonjs

I get

lib/typings/bluebird/bluebird.d.ts(705,9): error TS2300: Duplicate identifier 'concurrency'.
lib/typings/bluebird/bluebird.d.ts(708,9): error TS2300: Duplicate identifier 'spread'.
lib/typings/bluebird/bluebird.d.ts(711,9): error TS2300: Duplicate identifier 'suffix'.
typings/bluebird/bluebird.d.ts(705,9): error TS2300: Duplicate identifier 'concurrency'.
typings/bluebird/bluebird.d.ts(708,9): error TS2300: Duplicate identifier 'spread'.
typings/bluebird/bluebird.d.ts(711,9): error TS2300: Duplicate identifier 'suffix'.

Tools like npm seem to be able to handle this situation. The only way I can get typescript to handle it is by having a single tsd.json file and corresponding typings folder at the root of my project and having all the typescript definitions live there. Is that the generally accepted way to structure things?

[born2net]

+1 + 1 + 1... please add ignoreDups flag

[mhegazy]

The duplicate identifier is a symptom of another issue. i would like to understand the issue a bit more. Can you elaborate on why you need to copies of bluebird.d.ts (lib/typings/bluebird/bluebird.d.ts and typings/bluebird/bluebird.d.ts), why not have two tsconfig.json and call the compiler twice, once for lib, and once for server?

[born2net]

I beleive the issue has to do with the trasnpiler not respecting the exclude as in:

 "exclude": [
    "node_modules",
    "/node_modules",
    "../node_modules",
    "*node_modules*",
    "/node_modules*",
    "angular2",
    "rxjs",
    "typings"
  ],

since as you can see from my attached image, all issues are a result of the TS still inspecting the node_modules dir

[mhegazy]

"exclude" only excludes files in your folder, and its subfolders from being automatically included int he compilation. if you import a module in your code, the compiler will have to pull it in (e.g. import {..} from "angular2\angular2"). if you want to disable this use--noResolve`.

can you share your project so that i can understand the project setup?

[born2net]

sure: https://github.com/born2net/ng2Boilerplater-webpack

[born2net]

FYI noResolve the core libs wont resolve...

[davidleureka]

@mhegazy, it's quite possible that I'm simply not using the compiler the way it was intended to be used. I'm actually using the one built into WebStorm. My (probably incorrect) assumption was that I could compile my "main" file (server.ts) and the compiler would handle the references to other code recursively. Similar to how it works in a language like C++ with #include statements.

Can you elaborate more on your recommendation on how it should be structured? An example or reference would be helpful.

[mhegazy]

@born2net I think i understand the issue now. the main problem is that two packages you are including angular2 and ng2-translate both introduce the same global scope definitions.

//CC @alexegel from the angular2 team if he has any recommendations here.

Additionally, you were including locally some typings files, like node.d.ts that angular2 packages ships another verison of.

I have a PR out for your repo to work around that and demonstrate the issue at: https://github.com/born2net/ng2Boilerplater-webpack/pull/1

At the core, this is the same issue as #4665. @vladima is looking into a fix here.

[mhegazy]

@davidleureka can you share your project setup, so that i can understand the problem before making any recommendations.