//// [typeLiteralCallback.ts]
interface Foo<T> {
    reject(arg: T): void ;
}
var foo: Foo<string>

interface bar<T> {
    fail(func: (arg: T) => void ): void ;
    fail2(func: { (arg: T): void ; }): void ;
}
var test: bar<string>;

test.fail(arg => foo.reject(arg));
test.fail2(arg => foo.reject(arg));  // Should be OK.  Was: Error: Supplied parameters do not match any signature of call target


//// [typeLiteralCallback.js]
var foo;
var test;
test.fail(function (arg) { return foo.reject(arg); });
test.fail2(function (arg) { return foo.reject(arg); });