diff --git a/core/imageboard/image.php b/core/imageboard/image.php
index f9dfbefc..af5b7c60 100644
--- a/core/imageboard/image.php
+++ b/core/imageboard/image.php
@@ -734,7 +734,7 @@ class Image
                         $database->scoreql_to_sql(
                             "INSERT INTO image_tags(image_id, tag_id)
 							VALUES(:id, (SELECT id FROM tags WHERE SCORE_STRNORM(tag) = SCORE_STRNORM(:tag)))"
-                    ),
+                        ),
                         ["id"=>$this->id, "tag"=>$tag]
                     );
                 } else {
diff --git a/core/user.php b/core/user.php
index 91329542..4b746a78 100644
--- a/core/user.php
+++ b/core/user.php
@@ -103,6 +103,16 @@ class User
         return is_null($row) ? null : new User($row);
     }
 
+    public static function name_to_id(string $name): int
+    {
+        $u = User::by_name($name);
+        if (is_null($u)) {
+            throw SCoreException("Can't find any user named " . html_escape($name));
+        } else {
+            return $u->id;
+        }
+    }
+
     public static function by_name_and_pass(string $name, string $pass): ?User
     {
         $my_user = User::by_name($name);
diff --git a/ext/comment/main.php b/ext/comment/main.php
index e0d31a03..2b954331 100644
--- a/ext/comment/main.php
+++ b/ext/comment/main.php
@@ -347,13 +347,7 @@ class CommentList extends Extension
             $comments = $matches[2];
             $event->add_querylet(new Querylet("images.id IN (SELECT DISTINCT image_id FROM comments GROUP BY image_id HAVING count(image_id) $cmp $comments)"));
         } elseif (preg_match("/^commented_by[=|:](.*)$/i", $event->term, $matches)) {
-            $my_user = User::by_name($matches[1]);
-            if (!is_null($my_user)) {
-                $user_id = $my_user->id;
-            } else {
-                $user_id = -1;
-            }
-
+            $user_id = User::name_to_id($matches[1]);
             $event->add_querylet(new Querylet("images.id IN (SELECT image_id FROM comments WHERE owner_id = $user_id)"));
         } elseif (preg_match("/^commented_by_userno[=|:]([0-9]+)$/i", $event->term, $matches)) {
             $user_id = int_escape($matches[1]);
diff --git a/ext/favorites/main.php b/ext/favorites/main.php
index 3772f8c8..0c54382b 100644
--- a/ext/favorites/main.php
+++ b/ext/favorites/main.php
@@ -120,13 +120,7 @@ class Favorites extends Extension
             $favorites = $matches[2];
             $event->add_querylet(new Querylet("images.id IN (SELECT id FROM images WHERE favorites $cmp $favorites)"));
         } elseif (preg_match("/^favorited_by[=|:](.*)$/i", $event->term, $matches)) {
-            $my_user = User::by_name($matches[1]);
-            if (!is_null($my_user)) {
-                $user_id = $my_user->id;
-            } else {
-                $user_id = -1;
-            }
-
+            $user_id = User::name_to_id($matches[1]);
             $event->add_querylet(new Querylet("images.id IN (SELECT image_id FROM user_favorites WHERE user_id = $user_id)"));
         } elseif (preg_match("/^favorited_by_userno[=|:](\d+)$/i", $event->term, $matches)) {
             $user_id = int_escape($matches[1]);
diff --git a/ext/notes/main.php b/ext/notes/main.php
index a69cb6ea..702603bb 100644
--- a/ext/notes/main.php
+++ b/ext/notes/main.php
@@ -194,13 +194,7 @@ class Notes extends Extension
             $notes = $matches[2];
             $event->add_querylet(new Querylet("images.id IN (SELECT id FROM images WHERE notes $cmp $notes)"));
         } elseif (preg_match("/^notes_by[=|:](.*)$/i", $event->term, $matches)) {
-            $my_user = User::by_name($matches[1]);
-            if (!is_null($my_user)) {
-                $user_id = $my_user->id;
-            } else {
-                $user_id = -1;
-            }
-
+            $user_id = User::name_to_id($matches[1]);
             $event->add_querylet(new Querylet("images.id IN (SELECT image_id FROM notes WHERE user_id = $user_id)"));
         } elseif (preg_match("/^(notes_by_userno|notes_by_user_id)[=|:](\d+)$/i", $event->term, $matches)) {
             $user_id = int_escape($matches[2]);
diff --git a/ext/user/main.php b/ext/user/main.php
index bfcc0423..9ac332e9 100644
--- a/ext/user/main.php
+++ b/ext/user/main.php
@@ -296,12 +296,7 @@ class UserPage extends Extension
 
         $matches = [];
         if (preg_match("/^(?:poster|user)[=|:](.*)$/i", $event->term, $matches)) {
-            $duser = User::by_name($matches[1]);
-            if (!is_null($duser)) {
-                $user_id = $duser->id;
-            } else {
-                $user_id = -1;
-            }
+            $user_id = User::name_to_id($matches[1]);
             $event->add_querylet(new Querylet("images.owner_id = $user_id"));
         } elseif (preg_match("/^(?:poster|user)_id[=|:]([0-9]+)$/i", $event->term, $matches)) {
             $user_id = int_escape($matches[1]);