==== tests/cases/compiler/genericChainedCalls.ts (2 errors) ====
    interface I1<T> {
        func<U>(callback: (value: T) => U): I1<T>;
    }
     
    declare var v1: I1<number>;
     
    var r1 = v1.func(num => num.toString()) 
               .func(str => str.length) // error, number doesn't have a length
                                ~~~~~~
!!! Property 'length' does not exist on type 'number'.
               .func(num => num.toString())
     
    var s1 = v1.func(num => num.toString()) 
    var s2 = s1.func(str => str.length) // should also error
                                ~~~~~~
!!! Property 'length' does not exist on type 'number'.
    var s3 = s2.func(num => num.toString())