error TS5053: Option 'allowJs' cannot be specified with option 'isolatedDeclarations'.
a.js(4,9): error TS9013: Expression type can't be inferred with --isolatedDeclarations.


!!! error TS5053: Option 'allowJs' cannot be specified with option 'isolatedDeclarations'.
==== a.js (1 errors) ====
    function foo() { return 1; }
    export class C {
        constructor() {
            this.x = foo();
            ~~~~~~~~~~~~~~
!!! error TS9013: Expression type can't be inferred with --isolatedDeclarations.
        }
    }
    