X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~mdw/git/sod/blobdiff_plain/aa14a4cddcb96b681d5c19a2ec8bad382f43b264..239fa5bd3dff0b38b0cebdd3438311f21c24ba4f:/src/module-impl.lisp

diff --git a/src/module-impl.lisp b/src/module-impl.lisp
index 753ca0a..5343ad0 100644
--- a/src/module-impl.lisp
+++ b/src/module-impl.lisp
@@ -91,6 +91,19 @@ (defun build-module
       (when (and truename (not (eq (module-state *module*) t)))
 	(remhash truename *module-map*)))))
 
+(defun call-with-temporary-module (thunk)
+  "Invoke THUNK in the context of a temporary module, returning its values.
+
+   This is mainly useful for testing things which depend on module variables.
+   This is the functionality underlying `with-temporary-module'."
+  (let ((*module* (make-instance 'module
+				 :name "<temp>"
+				 :state nil)))
+    (call-with-module-environment
+     (lambda ()
+       (module-import *builtin-module*)
+       (funcall thunk)))))
+
 ;;;--------------------------------------------------------------------------
 ;;; Type definitions.