b.ts(1,8): error TS18060: Deferred imports are only supported when the '--module' flag is set to 'esnext' or 'preserve'.


==== a.ts (0 errors) ====
    export function foo() {
        console.log("foo from a");
    }
    
==== b.ts (1 errors) ====
    import defer * as aNs from "./a.js";
           ~~~~~~~~~~~~~~
!!! error TS18060: Deferred imports are only supported when the '--module' flag is set to 'esnext' or 'preserve'.
    
    aNs.foo();