Object

[gautamreloaded]

What does object.method1().method2() mean?

[cire]

Invoke method2 on the object returned by object.method1.

[z05DSL3A]

It is called method chaining:
http://www.parashift.com/c++-faq/method-chaining.html

[keskiverto]

The object must have a type, say T.
Each function has a type too; parameter types and return type.

Type T apparently has a member function T::method1(). No parameters, but some return type. Say U. U T::method1(), or in C++11 syntax auto T::method1() -> U.

Type U apparently has member function U::method2(). The call to T::method1() returns an unnamed temporary object of type U, so it is possible to call a member of that object.


If you have seen the code with that expression, then you should have access to the type definitions as well, and could backtrack every type.