Convert `filter` from a function to a macro

Doesn't make a big difference, just for fun. I like the idea of a
compile-time version of this since it's essentially just renaming
`remove-if-not`.

Move it to a new file so we can include it before it's used in
`main.lisp`.

3 files changed, 5 insertions, 3 deletions

diff --git a/l/extreload.asd b/l/extreload.asd
index 5edcdd7..21a5329 100644
--- a/l/extreload.asd
+++ b/l/extreload.asd
@@ -5,6 +5,7 @@
   :components ((:module "src"
                 :serial t
                 :components ((:file "package")
+                             (:file "macro")
                              (:file "main"))))
 
   :build-operation "program-op"
diff --git a/l/src/macro.lisp b/l/src/macro.lisp
new file mode 100644
index 0000000..4d69294
--- /dev/null
+++ b/l/src/macro.lisp
@@ -0,0 +1,4 @@
+(in-package :extreload)
+
+(defmacro filter (predicate list-form)
+  `(remove-if-not ,predicate ,list-form))
diff --git a/l/src/main.lisp b/l/src/main.lisp
index 6abe363..42c0ccd 100644
--- a/l/src/main.lisp
+++ b/l/src/main.lisp
@@ -91,6 +91,3 @@
                       "background_page")))
 
     (filter #'extensionp targets)))
-
-(defun filter (predicate list-form)
-  (remove-if-not predicate list-form))