Ionic-framework: TS strict null checks compliant

[manucorporat]

Once ionic uses Angular 4, we should make Ionic compliant with the --strictNullChecks option of the typescript transpiler.

• Reduce technical debt
• Better static analysis for ionic
• Fix hidden bugs

Ref:
https://github.com/angular/angular/blob/master/CHANGELOG.md#400-rc1-2017-02-24
https://www.typescriptlang.org/docs/handbook/release-notes/typescript-2-0.html

Duplicate of https://github.com/driftyco/ionic/issues/9456

[adrm]

I tried to enable strict mode in my project ("strict": true in "compilerOptions" section of tsconfig.json) and had this error from one of your files.

node_modules/ionic-angular/util/base-input.d.ts(23,22): error TS2420: Class 'BaseInput<T>' incorrectly implements interface 'CommonInput<T>'.
  Types of property 'ionFocus' are incompatible.
    Type 'EventEmitter<BaseInput<T>>' is not assignable to type 'EventEmitter<CommonInput<T>>'.
      Types of property 'observers' are incompatible.
        Type 'Observer<BaseInput<T>>[]' is not assignable to type 'Observer<CommonInput<T>>[]'.
          Type 'Observer<BaseInput<T>>' is not assignable to type 'Observer<CommonInput<T>>'.
            Type 'CommonInput<T>' is not assignable to type 'BaseInput<T>'.

This prevents me from using strict mode in my project. Is there any workaround or ETA for this?

Thanks

[adrm]

The error in ionic serve is this:

I think we are loosing a great part of the benefit of using Typescript if we are not able to use it in strict mode. Please consider fixing this one error.

[manucorporat]

Ionic 4 will address this problems

[shinriyo]

Why Closed? Did you resolved? just removed "strict"?

[shinriyo]

Ah... I skipped to read @manucorporat 's message, I should just wait it, shouldn't I?

[ionitron-bot[bot]]

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