error TS5107: Option 'module=System' is deprecated and will stop functioning in TypeScript 7.0. Specify compilerOption '"ignoreDeprecations": "6.0"' to silence this error.
bar.ts(3,5): error TS2564: Property 'b' has no initializer and is not definitely assigned in the constructor.
foo.ts(2,5): error TS2564: Property 'a' has no initializer and is not definitely assigned in the constructor.


!!! error TS5107: Option 'module=System' is deprecated and will stop functioning in TypeScript 7.0. Specify compilerOption '"ignoreDeprecations": "6.0"' to silence this error.
==== foo.ts (1 errors) ====
    export class Foo {
        a: string;
        ~
!!! error TS2564: Property 'a' has no initializer and is not definitely assigned in the constructor.
    }
    
==== bar.ts (1 errors) ====
    import {Foo} from './foo';
    export class Bar extends Foo {
        b: string;
        ~
!!! error TS2564: Property 'b' has no initializer and is not definitely assigned in the constructor.
    }