diff --git a/zipapps/main.py b/zipapps/main.py
index b3c0a1a..fa7cae9 100644
--- a/zipapps/main.py
+++ b/zipapps/main.py
@@ -370,7 +370,8 @@ def prepare_active_zipapps(self):
 
         def make_runner():
             if self.main:
-                if re.match(r"^\w+(\.\w+)?(:\w+)?$", self.main):
+                pattern = r"^\w+(\.\w+)?(:\w+)?$"
+                if re.match(pattern, self.main):
                     module, _, function = self.main.partition(":")
                     if module:
                         # main may be: 'module.py:main' or 'module.submodule:main'
@@ -382,12 +383,12 @@ def make_runner():
                         if function:
                             runner += f"; {module}.{function}()"
                         self._log(
-                            f"[INFO]: -m: matches re.match(r'^\w+(\.\w+)?(:\w+)?$', self.main), add as `{runner}`."
+                            f"[INFO]: -m: matches re.match(r'{pattern}', self.main), add as `{runner}`."
                         )
                         return runner
                 else:
                     self._log(
-                        f"[INFO]: -m: not matches re.match(r'^\w+(\.\w+)?(:\w+)?$', self.main), add as raw code `{self.main}`."
+                        f"[INFO]: -m: not matches re.match(r'{pattern}', self.main), add as raw code `{self.main}`."
                     )
                     return self.main
             return ""