diff --git a/php/src/cache/CacheFile.php b/php/src/cache/CacheFile.php
index 15821d5..9fa95b2 100644
--- a/php/src/cache/CacheFile.php
+++ b/php/src/cache/CacheFile.php
@@ -178,13 +178,14 @@ class CacheFile extends SharedFile {
   }
 
   protected function afterAction() {
+    # égalité non stricte pour start et duration
     $modified = false;
     if ($this->start != $this->ostart) $modified = true;
     $duration = $this->duration;
     $oduration = $this->oduration;
     if ($duration === null || $oduration === null) $modified = true;
     elseif ($duration->getDest() != $oduration->getDest()) $modified = true;
-    # égalité stricte uniquement pour $data et $datafiles
+    # égalité stricte pour $data
     if ($this->data !== $this->odata) $modified = true;
     if ($modified && !$this->readonly) {
       $this->lockWrite();
@@ -288,20 +289,20 @@ class CacheFile extends SharedFile {
     return $this;
   }
 
-  function get($data=null, bool $noCache=false) {
-    return $this->action(function () use ($data, $noCache) {
-      return $this->refreshData($data, $noCache);
+  function get($key=null, bool $noCache=false) {
+    return $this->action(function () use ($key, $noCache) {
+      return $this->refreshData($key, $noCache);
     });
   }
 
-  function all($data=null, bool $noCache=false): ?iterable {
-    $data = $this->get($data, $noCache);
+  function all($key=null, bool $noCache=false): ?iterable {
+    $data = $this->get($key, $noCache);
     if ($data !== null && !is_iterable($data)) $data = [$data];
     return $data;
   }
 
-  function delete($data=null): void {
-    $source = $this->sources[$data] ?? null;
+  function delete($key=null): void {
+    $source = $this->sources[$key] ?? null;
     if ($source !== null) $source->delete();
   }