I’ll cover those data structures in future chapters, but while we’re on the topic of assignment, you should note that can assign any place a value. As I cover the different composite data structures, I’ll point out which functions can serve as “**SETF**able places.” The short version, however, is if you need to assign a value to a place, **SETF** is almost certainly the tool to use. It’s even possible to extend **SETF** to allow it to assign to user-defined places though I won’t cover that.16

Table 6-1. Assignment with = in Other Languages

Note that **SETF**ing a place that’s part of a larger object has the same semantics as ing a variable: the place is modified without any effect on the object that was previously stored in the place. Again, this is similar to how **=** behaves in Java, Perl, and Python.18