Packages

Introduction

All public package operations, such as intern, find-symbol, and defpackage, are protected by a global package lock. The package lock is a read-write lock allowing many package operations to proceed in parallel such as find-symbol.

The package iteration macros only hold the package lock while initialising and executed the body without the package lock held. The iterated symbols do not necessarily reflect changes to the packages after the iteration has been initialised, but iteration is safe against package table rehashing etc.