import

(import symbols &optional package)

Makes symbols (a symbol or a list of them) accessible unqualified in package (the current package by default): a later bare name resolves to the imported symbol rather than to a fresh symbol of the importing package, and find-symbol answers it with status :internal. Returns t. It is the runtime form of the defpackage :import-from clause. Each symbol is imported from its home -- a package-qualified symbol from the package its qualifier names, a bare one from cl-user (or cl, for a standard name) -- and a symbol the package already owns is a no-op. A different symbol of the same name already present in the package (owned or imported, not merely inherited) is a name conflict and signals a catchable package-error; shadowing-import is the form that displaces it instead. An unknown package signals (No such package: NOSUCH).

Packages are resolved at read/compile time here (see Packages), so a literal top-level call is consumed at compile time like in-package and takes effect for the forms that follow it — which is what makes it work on every backend. A runtime-computed call (a symbol built at run time) works on the interpreter, and on every backend for a package the program created with make-package, whose member table records the import.