export

(export symbols &optional package)

Makes symbols (a symbol or a list of them) external in package (the current package by default), so they are visible unqualified through a use-package and spell with one colon rather than two. Returns t. It is the runtime form of the defpackage :export clause; unexport is the inverse.

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 list built at run time) works on the interpreter only.

Exporting changes only accessibility, so it may come before or after the definitions it publishes — the everyday shape of a Common Lisp file, which defines its functions and exports them at the end, works:

A reference written before the export is still an error, as in Common Lisp — the symbol is not external yet at that point.

One deviation: a symbol exported after it was first named prints with the double colon (greeter3::hi), because the qualifier is part of the stored symbol here rather than recomputed at print time. Both spellings name the same symbol.