If I understood the doc correctly, the visitation is supposed to be compile-time, that is, v.apply_visitor( print_type() ) is already "char" before the program start... Is this right?

The visitation is "compile-time" in the sense that it's type-safe. "v.apply_visitor( print_type() )" might or might not be substituted by "char" depending on your optimization switches. In MSVC9, with optimization (/O2) it produces the following output: 00402B3C push offset string "char" (419368h) 00402B41 push offset std::cout (420BC8h) 00402B46 call std::operator<< (4027F0h) So "v.apply_visitor( print_type() )" is really substituted by "char" in compile-time. But without the optimization you'll go through all the visitation calls.

If so, is there a way to see this in the binary executable file? Maybe viewing symbols?

In MSVC - compile the program, step into main (or set breakpoint), then go to Debug-->Windows-->Dissasembly.