provide

(provide module-name)

Marks a module as loaded, so a later require of the same name returns without loading any file. Returns the module name as a symbol; module-name is a designator (keyword, symbol, or string), and providing an already-provided name is a no-op. A file loaded by require is expected to call provide itself, conventionally as its first form (which also lets mutually requiring files terminate).

The backend split mirrors require: an ordinary runtime function on the interpreter, and a literal, top-level compile-time directive on the JVM/WASM compile path (a nested or computed provide is a compile error). The Common Lisp *modules* variable is not available.

The require returns immediately because the module was already provided in the same program — no my-module.lisp file is looked up.