Error due to reference to types core-js

[davinkevin]

Hello,

I'm working on the tour of heroes, implementing it with the AngularCLI and the last version of angular (2.1.0) => https://github.com/davinkevin/Angular2-TourOfHeroes.

So, at the part6 of the TourOfHeroes, I install the in-memory-web-api, but after serving the app I am facing the following error :

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/angular-in-memory-web-api/in-memory-backend.service.d.ts:1:0
Cannot find type definition file for 'core-js'.

The line 1 of the file https://github.com/angular/in-memory-web-api/blob/master/in-memory-backend.service.d.ts#L1 try to load the type file for core-js, but it is only a dev dependency, so not present in my project.

If I add this by installing with npm i -D @types/core-js I have a lot more errors, due to conflicts with es2015.core types definition of Typescript.

** NG Live Development Server is running on http://localhost:4200. **
4569ms building modules
34ms sealing
0ms optimizing
0ms basic module optimization
78ms module optimization
1ms advanced module optimization
12ms basic chunk optimization
0ms chunk optimization
3ms advanced chunk optimization
1ms module and chunk tree optimization
127ms module reviving
9ms module order optimization
4ms module id optimization
3ms chunk reviving
0ms chunk order optimization
11ms chunk id optimization
59ms hashing
0ms module assets processing
165ms chunk assets processing
3ms additional chunk assets processing
0ms recording
0ms additional asset processing
1341ms chunk asset optimization
1050ms asset optimization
42ms emitting
Hash: 0f90a2d2ddfcb98dd1e0
Version: webpack 2.1.0-beta.25
Time: 7531ms
           Asset       Size  Chunks             Chunk Names
  main.bundle.js    3.09 MB    0, 2  [emitted]  main
styles.bundle.js    10.7 kB    1, 2  [emitted]  styles
       inline.js    5.53 kB       2  [emitted]  inline
        main.map    3.21 MB    0, 2  [emitted]  main
      styles.map    14.8 kB    1, 2  [emitted]  styles
      inline.map    5.59 kB       2  [emitted]  inline
      index.html  485 bytes          [emitted]

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:21:13
Duplicate identifier 'PropertyKey'.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:85:4
All declarations of 'name' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:145:4
Subsequent variable declarations must have the same type.  Variable '[Symbol.unscopables]' must be of type '{ copyWithin: boolean; entries: boolean; fill: boolean; find: boolean; findIndex: boolean; keys: ...', but here has type 'any'.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:262:4
All declarations of 'flags' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:276:4
All declarations of 'EPSILON' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:311:4
All declarations of 'MAX_SAFE_INTEGER' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:318:4
All declarations of 'MIN_SAFE_INTEGER' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:457:4
Subsequent variable declarations must have the same type.  Variable '[Symbol.toStringTag]' must be of type '"Symbol"', but here has type 'string'.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:457:4
All declarations of '[Symbol.toStringTag]' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:464:4
All declarations of 'prototype' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:492:4
All declarations of 'hasInstance' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:498:4
All declarations of 'isConcatSpreadable' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:504:4
All declarations of 'iterator' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:510:4
All declarations of 'match' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:516:4
All declarations of 'replace' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:522:4
All declarations of 'search' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:528:4
All declarations of 'species' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:534:4
All declarations of 'split' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:540:4
All declarations of 'toPrimitive' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:546:4
All declarations of 'toStringTag' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:552:4
All declarations of 'unscopables' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:609:4
Subsequent variable declarations must have the same type.  Variable '[Symbol.toStringTag]' must be of type '"Math"', but here has type 'string'.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:609:4
All declarations of '[Symbol.toStringTag]' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:613:4
Subsequent variable declarations must have the same type.  Variable '[Symbol.toStringTag]' must be of type '"JSON"', but here has type 'string'.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:613:4
All declarations of '[Symbol.toStringTag]' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:628:4
All declarations of 'size' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:634:4
All declarations of 'prototype' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:645:4
All declarations of 'size' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:651:4
All declarations of 'prototype' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:666:4
All declarations of 'prototype' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:680:4
All declarations of 'prototype' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:692:4
All declarations of 'value' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/@types/core-js/index.d.ts:804:4
All declarations of 'prototype' must have identical modifiers.

ERROR in [default] /Users/kevin/Workspace/Angular2-TourOfHeroes/node_modules/typescript/lib/lib.es2015.core.d.ts:17:13
Duplicate identifier 'PropertyKey'.
Child html-webpack-plugin for "index.html":
         Asset     Size  Chunks       Chunk Names
    index.html  2.82 kB       0
webpack: bundle is now VALID.

What can we do to suppress this error ?

Thanks ;)

[maximeburri]

The problem seems to come from the line /// <reference types="core-js" /> of in-memory-backend.service.d.ts.
I don't know the utility of this line but its deletion seems to fix the problem.

[davinkevin]

Yeah, removing it fix the problem...

But the problem is worse than I though, because it cause an error during the ng serve --aot true and a corrupted build with ng build --aot true.

[cqst]

error appears since "angular-in-memory-web-api": "0.1.14"

try to replace with "angular-in-memory-web-api": "0.1.13" in package.json

fix pb for me

[tomwanzek]

I experienced the same issue with missing core-js typings after upgrading an angular-cli beta.18 project to beta.19-3. Thx @cqst. for now, reverting back to "angular-in-memory-web-api": "0.1.13" fixed the issue.

[pulsar256]

Downgrading to .18 did not help (re: ng-lightning/ng-lightning#265)

ᐅ rm node_modules -Rfv
ᐅ yarn install
ᐅ ng version
angular-cli: 1.0.0-beta.18
node: 7.1.0
os: linux x64
ᐅ ng build
(...)
Error in bail mode: [default] /(...)/node_modules/ng-lightning/config/config.d.ts:1:0 
Cannot find type definition file for 'core-js'.
(...)

workaround by removing the core-js reference from the affected dependencies (ng-lightning in my case) could be verified.

[rochavic]

I had the same issue...

My environment:

angular-cli: 1.0.0-beta.19-3
node: 6.8.1
os: win32 x64

Steps to fix Tour of Heroes with angular-cli (in my case):

1 - npm i angular-in-memory-web-api
2 - npm i @types/core-js
3 - Edit package.json file and add the dependency: angular-in-memory-web-api": "0.1.14"
4 - On tsconfig.json, change lib settings to: "lib": ["es5", "dom"],

The trick: http://blog.mgechev.com/2016/03/28/ambient-type-definitions-duplicate-identifier-typescript-fix/

[meiordac]

Downgrading to "angular-in-memory-web-api": "0.1.13" worked fine