diff --git a/nur_src/v/bs3/Bs3IconManager.php b/nur_src/v/bs3/Bs3IconManager.php
index 0465df0..a81cbbd 100644
--- a/nur_src/v/bs3/Bs3IconManager.php
+++ b/nur_src/v/bs3/Bs3IconManager.php
@@ -15,6 +15,7 @@ class Bs3IconManager implements IIconManager {
     "config" => "cog",
     "save" => "floppy-disk",
     "download" => "download-alt",
+    "upload" => "cloud-upload",
     "new_window",
     "mail" => "enveloppe",
     "search",
@@ -84,6 +85,7 @@ EOT;
     'config' => 'cog',
     'save' => 'floppy-disk',
     'download' => 'download-alt',
+    'upload' => 'cloud-upload',
     'new_window' => 'new-window',
     'mail' => 'enveloppe',
     'search' => 'search',
@@ -138,6 +140,7 @@ EOT;
   const CONFIG = /*autogen*/['<span class="glyphicon glyphicon-cog" aria-hidden="true"></span>'];
   const SAVE = /*autogen*/['<span class="glyphicon glyphicon-floppy-disk" aria-hidden="true"></span>'];
   const DOWNLOAD = /*autogen*/['<span class="glyphicon glyphicon-download-alt" aria-hidden="true"></span>'];
+  const UPLOAD = /*autogen*/['<span class="glyphicon glyphicon-cloud-upload" aria-hidden="true"></span>'];
   const NEW_WINDOW = /*autogen*/['<span class="glyphicon glyphicon-new-window" aria-hidden="true"></span>'];
   const MAIL = /*autogen*/['<span class="glyphicon glyphicon-enveloppe" aria-hidden="true"></span>'];
   const SEARCH = /*autogen*/['<span class="glyphicon glyphicon-search" aria-hidden="true"></span>'];
diff --git a/src/A.php b/src/A.php
index 225f668..a610fa5 100644
--- a/src/A.php
+++ b/src/A.php
@@ -64,7 +64,7 @@ class A {
     $dest = cl::mpselect($dest, $merge, $pkeys);
   }
 
-  static final function append_nn(?array &$dest, $value, $key=null) {
+  static final function set_nn(?array &$dest, $key, $value) {
     if ($value !== null) {
       if ($key === null) $dest[] = $value;
       else $dest[$key] = $value;
@@ -72,7 +72,11 @@ class A {
     return $value;
   }
 
-  static final function append_nz(?array &$dest, $value, $key=null) {
+  static final function append_nn(?array &$dest, $value, $key=null) {
+    return self::set_nn($dest, $key, $value);
+  }
+
+  static final function set_nz(?array &$dest, $key, $value) {
     if ($value !== null && $value !== false) {
       if ($key === null) $dest[] = $value;
       else $dest[$key] = $value;
@@ -80,6 +84,10 @@ class A {
     return $value;
   }
 
+  static final function append_nz(?array &$dest, $value, $key=null) {
+    return self::set_nz($dest, $key, $value);
+  }
+
   static final function prepend_nn(?array &$dest, $value) {
     if ($value !== null) {
       if ($dest === null) $dest = [];
@@ -95,4 +103,43 @@ class A {
     }
     return $value;
   }
+
+  static final function replace_nx(?array &$dest, $key, $value) {
+    if ($dest !== null && !array_key_exists($key, $dest)) {
+      return $dest[$key] = $value;
+    } else {
+      return $dest[$key] ?? null;
+    }
+  }
+
+  static final function replace_n(?array &$dest, $key, $value) {
+    $pvalue = $dest[$key] ?? null;
+    if ($pvalue === null) $dest[$key] = $value;
+    return $pvalue;
+  }
+
+  static final function replace_z(?array &$dest, $key, $value) {
+    $pvalue = $dest[$key] ?? null;
+    if ($pvalue === null || $pvalue === false) $dest[$key] = $value;
+    return $pvalue;
+  }
+
+  static final function pop(?array $dest, $key, $default=null) {
+    if ($dest === null) return $default;
+    if ($key === null) return array_pop($dest);
+    $value = $dest[$key] ?? $default;
+    unset($dest[$key]);
+    return $value;
+  }
+
+  static final function popx(?array $dest, ?array $keys): array {
+    $values = [];
+    if ($dest === null) return $values;
+    if ($keys === null) return $values;
+    foreach ($keys as $key) {
+      $values[$key] = self::pop($dest, $key);
+    }
+    return $values;
+  }
+
 }
diff --git a/src/file/csv/AbstractReader.php b/src/file/csv/AbstractReader.php
index 82bd29d..7ef5237 100644
--- a/src/file/csv/AbstractReader.php
+++ b/src/file/csv/AbstractReader.php
@@ -18,6 +18,7 @@ abstract class AbstractReader  implements IReader {
     $this->schema = $params["schema"] ?? static::SCHEMA;
     $this->headers = $params["headers"] ?? static::HEADERS;
     $this->input = $params["input"] ?? static::INPUT;
+    $this->parseEmptyAsNull = boolval($params["empty_as_null"] ?? true);
   }
 
   protected ?array $schema;
@@ -26,6 +27,8 @@ abstract class AbstractReader  implements IReader {
 
   protected $input;
 
+  protected bool $parseEmptyAsNull;
+
   protected int $isrc = 0, $idest = 0;
 
   protected function cook(array &$row): bool {
@@ -45,10 +48,14 @@ abstract class AbstractReader  implements IReader {
   }
 
   protected function verifixCol(&$col): void {
-    # conversion Date et DateTime
-    if (DateTime::isa_datetime($col, true)) {
+    if ($col === "" && $this->parseEmptyAsNull) {
+      # valeur vide --> null
+      $col = null;
+    } elseif (DateTime::isa_datetime($col, true)) {
+      # datetime
       $col = new DateTime($col);
     } elseif (DateTime::isa_date($col, true)) {
+      # date
       $col = new Date($col);
     }
   }