rxjs/Subject.d.ts error : Class 'Subject' incorrectly extends base class 'Observable'

Question

I extracted sample template code from this tutorial and did below two steps to get started -

1. npm install // worked fine and created node_modules folder

Answer 1

Keep the noStrictGeneric option true in tsconfig.config file

{
    "compilerOptions": {
        "noStrictGenericChecks": true
    }
}

Answer 2

I found same problem and I solved it by using "rxjs": "5.4.1", "typescript": "~2.4.0" and adding "noStrictGenericChecks": true into tsconfig.json.

Answer 3

Now we dont need the ionic-native module - we only need @ionic-native/core. Run

npm uninstall ionic-native --save

It will solve Your Problem..

Answer 4

An admitted band-aid approach is to add the following to your tsconfig.json file until the RxJS folks decide what they want to do about the error when using TypeScript 2.4.1 :

"compilerOptions": {

    "skipLibCheck": true,

 }

Answer 5

RxJS 6 will have this fixed, but as a temporary workaround, you can use the noStrictGenericChecks compiler option.

In tsconfig.json, put it in compilerOptions and set it to true.

{
    "compilerOptions": {
        "noStrictGenericChecks": true
    }
}

On the command line it's --noStrictGenericChecks.

Why it's happening:

TypeScript 2.4 has a strictness change, and Subject isn't lifting to the correct Observable. The signature really should have been

(operator: Operator) => Observable

This will be fixed in RxJS 6.

Answer 6

Add "noStrictGenericChecks": true in tsconfig.json file under "compilerOptions" node as shown in below image & build application. I have faced same error after adding this error resolved.