==== tests/cases/compiler/assignmentCompatability25.ts (1 errors) ====
    module __test1__ {
        export interface interfaceWithPublicAndOptional<T,U> { one: T; two?: U; };  var obj4: interfaceWithPublicAndOptional<number,string> = { one: 1 };;
        export var __val__obj4 = obj4;
    }
    module __test2__ {
        export var aa:{two:number;};;
        export var __val__aa = aa;
    }
    __test2__.__val__aa = __test1__.__val__obj4
    ~~~~~~~~~~~~~~~~~~~
!!! assignmentCompatability25.ts(9,1): error TS2012: Cannot convert '__test1__.interfaceWithPublicAndOptional<number, string>' to '{ two: number; }':
!!! 	Property 'two' defined as optional in type '__test1__.interfaceWithPublicAndOptional<T, U>', but is required in type '{ two: number; }'.