How can moment.js be imported with typescript?

peinearydevelopment picture peinearydevelopment · Apr 15, 2016 · Viewed 107.3k times · Source

I'm trying to learn Typescript. While I don't think it's relevant, I'm using VSCode for this demo.

I have a package.json that has these pieces in it:

{
  "devDependencies": {
    "gulp": "^3.9.1",
    "jspm": "^0.16.33",
    "typescript": "^1.8.10"
  },
  "jspm": {
    "moment": "npm:moment@^2.12.0"
  }
}

Then I have a Typescript class main.js like this:

import moment from 'moment';
export class Main {
}

My gulpfile.js looks like this:

var gulp = require('gulp');
var typescript = require('gulp-tsb');
var compilerOptions = {
                        "rootDir": "src/",
                        "sourceMap": true,
                        "target": "es5",
                        "module": "amd",
                        "declaration": false,
                        "noImplicitAny": false,
                        "noResolve": true,
                        "removeComments": true,
                        "noLib": false,
                        "emitDecoratorMetadata": true,
                        "experimentalDecorators": true
                      };
var typescriptCompiler = typescript.create(compilerOptions);
gulp.task('build', function() {
  return gulp.src('/src')
    .pipe(typescriptCompiler())
    .pipe(gulp.dest('/dest'));
});

When I run gulp build, I get the message: "../main.ts(1,25): Cannot file module 'moment'."

If I use import moment = require('moment'); then jspm will work and bring in the module when I run the application, but I'm still receiving the build error. I also tried:

npm install typings -g
typings install moment --ambient --save

Instead of making the problem better though, it got worse. Now I get the above error on build as well as the following: "../typings/browser/ambient/moment/index.d.ts(9,21): Cannot find namespace 'moment'."

If I go to the file provided by typings and add at the bottom of the file:

declare module "moment" { export = moment; }

I can get the second error to go away, but I still need the require statement to get moment to work in my main.ts file and am still getting the first build error.

Do I need to create my own .d.ts file for moment or is there just some setup piece I'm missing?

Answer

Aides picture Aides · Apr 15, 2016

Update

Apparently, moment now provides its own type definitions (according to sivabudh at least from 2.14.1 upwards), thus you do not need typings or @types at all.

import * as moment from 'moment' should load the type definitions provided with the npm package.

That said however, as said in moment/pull/3319#issuecomment-263752265 the moment team seems to have some issues in maintaining those definitions (they are still searching someone who maintains them).


You need to install moment typings without the --ambient flag.

Then include it using import * as moment from 'moment'