diff --git a/src/output/IMessenger.php b/src/output/IMessenger.php
index f645f11..aeceae9 100644
--- a/src/output/IMessenger.php
+++ b/src/output/IMessenger.php
@@ -6,6 +6,7 @@ namespace nur\sery\output;
  */
 interface IMessenger {
   const LEVEL_DEBUG = -1, LEVEL_NORMAL = 0, LEVEL_MAJOR = 1, LEVEL_NONE = 2;
+  const MIN_LEVEL = self::LEVEL_DEBUG, MAX_LEVEL = self::LEVEL_MAJOR;
 
   /** réinitialiser les paramètres de l'objet */
   function resetParams(?array $params=null): void;
diff --git a/src/output/TODO.md b/src/output/TODO.md
index 2f03b55..059a71d 100644
--- a/src/output/TODO.md
+++ b/src/output/TODO.md
@@ -2,8 +2,9 @@
 
 ## TOOD
 
-* [ ] affichage des exceptions en message technique.
-  si pas de message, prendre le message de l'exception par défaut
+* [ ] section(), title() et action() acceptent une fonction qui fait le travail
+  avec en premier argument l'instance de messenger, et qui termine l'objet
+  l'objet ensuite
 * [ ] possibilité de paramétrer le nom du fichier destination pour faire une
   rotation des logs
 * [ ] support quiet (uniquement major), very-quiet (aucun message n'est affiché)
diff --git a/src/output/std/StdMessenger.php b/src/output/std/StdMessenger.php
index 325e9b4..3bf925b 100644
--- a/src/output/std/StdMessenger.php
+++ b/src/output/std/StdMessenger.php
@@ -3,7 +3,10 @@ namespace nur\sery\output\std;
 
 use Exception;
 use nulib\cl;
+use nulib\ExceptionShadow;
+use nulib\UserException;
 use nur\sery\output\IMessenger;
+use Throwable;
 
 class StdMessenger implements IMessenger {
   const INDENT = "  ";
@@ -22,7 +25,12 @@ class StdMessenger implements IMessenger {
     "none" => self::LEVEL_NONE, "silent" => self::LEVEL_NONE,
   ];
 
-  protected static function verifix_level($level, int $max_level=self::LEVEL_MAJOR): int {
+  protected static function decr_level(int $level): int {
+    if (--$level < self::MIN_LEVEL) $level = self::MIN_LEVEL;
+    return $level;
+  }
+
+  protected static function verifix_level($level, int $max_level=self::MAX_LEVEL): int {
     if (!in_array($level, self::VALID_LEVELS, true)) {
       $level = cl::get(self::LEVEL_MAP, $level, $level);
     }
@@ -65,7 +73,7 @@ class StdMessenger implements IMessenger {
       "error" => ["debugE", "<color r>e</color><color -r>", "</color>"],
       "warn" => ["debugW", "<color y>w</color><color -y>", "</color>"],
       "note" => ["debugN", "<color b>i</color>", ""],
-      "info" => ["debugI", "<color @w>D</color><color w>", "</color>"],
+      "info" => ["debug", "<color @w>D</color><color w>", "</color>"],
       "step" => ["*", "<color @w>.</color>", ""],
       "print" => [null, null, null],
     ],
@@ -201,6 +209,18 @@ class StdMessenger implements IMessenger {
     return $level >= $this->minLevel;
   }
 
+  protected function getIndentLevel(bool $withActions=true): int {
+    $indentLevel = count($this->titles) - 1;
+    if ($indentLevel < 0) $indentLevel = 0;
+    if ($withActions) {
+      foreach ($this->actions as $action) {
+        if ($action["level"] < $this->minLevel) continue;
+        $indentLevel++;
+      }
+    }
+    return $indentLevel;
+  }
+
   protected function _printTitle(?string $linePrefix, int $level,
                                  string $type, $content,
                                  int $indentLevel, StdOutput $out): void {
@@ -319,8 +339,9 @@ class StdMessenger implements IMessenger {
     }
   }
 
-  protected function _printGeneric(int $level, string $type, $content, int $indentLevel, StdOutput $out): void {
-    $linePrefix = $this->getLinePrefix();
+  protected function _printGeneric(?string $linePrefix, int $level,
+                                   string $type, $content,
+                                   int $indentLevel, StdOutput $out): void {
     $prefixes = self::GENERIC_PREFIXES[$level][$type];
     if ($out->isColor()) {
       $prefix = $prefixes[1];
@@ -350,6 +371,53 @@ class StdMessenger implements IMessenger {
     }
   }
 
+  protected function _printGenericOrException(?int $level, string $type, $content, int $indentLevel, StdOutput $out): void {
+    $linePrefix = $this->getLinePrefix();
+    # si $content contient des exceptions, les afficher avec un level moindre
+    $exceptions = null;
+    if (is_array($content)) {
+      $valueContent = null;
+      foreach ($content as $value) {
+        if ($value instanceof Throwable || $value instanceof ExceptionShadow) {
+          $exceptions[] = $value;
+        } else {
+          $valueContent[] = $value;
+        }
+      }
+      $content = $valueContent;
+    } elseif ($content instanceof Throwable || $content instanceof ExceptionShadow) {
+      $exceptions[] = $content;
+      $content = null;
+    }
+
+    $printActions = true;
+    $showContent = $this->checkLevel($level);
+    if ($content !== null && $showContent) {
+      $this->printActions(); $printActions = false;
+      $this->_printGeneric($linePrefix, $level, $type, $content, $indentLevel, $out);
+    }
+    if ($exceptions !== null) {
+      $level1 = self::decr_level($level);
+      $showTraceback = $this->checkLevel($level1);
+      foreach ($exceptions as $exception) {
+        # tout d'abord userMessage
+        $userMessage = UserException::get_user_message($exception);
+        if ($userMessage !== null && $showContent) {
+          if ($printActions) { $this->printActions(); $printActions = false; }
+          $this->_printGeneric($linePrefix, $level, $type, $userMessage, $indentLevel, $out);
+        }
+        # puis summary et traceback
+        if ($showTraceback) {
+          if ($printActions) { $this->printActions(); $printActions = false; }
+          $summary = UserException::get_summary($exception);
+          $traceback = UserException::get_traceback($exception);
+          $this->_printGeneric($linePrefix, $level1, $type, $summary, $indentLevel, $out);
+          $this->_printGeneric($linePrefix, $level1, $type, $traceback, $indentLevel, $out);
+        }
+      }
+    }
+  }
+
   /** @var bool est-on dans une section? */
   protected $inSection;
 
@@ -370,7 +438,7 @@ class StdMessenger implements IMessenger {
 
   protected function printSection() {
     $section =& $this->section;
-    if ($section["print_content"]) {
+    if ($section !== null && $section["print_content"]) {
       $this->_printTitle(
         $section["line_prefix"], $section["level"],
         "section", $section["content"],
@@ -384,18 +452,6 @@ class StdMessenger implements IMessenger {
     $this->section = null;
   }
 
-  protected function getIndentLevel(bool $withActions=true): int {
-    $indentLevel = count($this->titles) - 1;
-    if ($indentLevel < 0) $indentLevel = 0;
-    if ($withActions) {
-      foreach ($this->actions as $action) {
-        if ($action["level"] < $this->minLevel) continue;
-        $indentLevel++;
-      }
-    }
-    return $indentLevel;
-  }
-
   /** @var array */
   protected $titles;
 
@@ -440,7 +496,10 @@ class StdMessenger implements IMessenger {
       }
       if ($title["print_descs"]) {
         foreach ($title["descs"] as $desc) {
-          $this->_printGeneric($desc["level"], "desc", $desc["content"], $indentLevel, $err);
+          $this->_printGeneric(
+            $desc["line_prefix"], $desc["level"],
+            "desc", $desc["content"],
+            $indentLevel, $err);
         }
         $title["descs"] = [];
         $title["print_descs"] = false;
@@ -511,10 +570,7 @@ class StdMessenger implements IMessenger {
   }
 
   function step($content, ?int $level=null): void {
-    if (!$this->checkLevel($level)) return;
-    if (!$this->actions) $this->action(null);
-    $this->printActions();
-    $this->_printGeneric($level, "step", $content, $this->getIndentLevel(), $this->err);
+    $this->_printGenericOrException($level, "step", $content, $this->getIndentLevel(), $this->err);
   }
 
   function asuccess($content=null): void {
@@ -552,33 +608,23 @@ class StdMessenger implements IMessenger {
   }
 
   function print($content, ?int $level=null): void {
-    if (!$this->checkLevel($level)) return;
-    $this->printActions();
-    $this->_printGeneric($level, "print", $content, $this->getIndentLevel(), $this->out);
+    $this->_printGenericOrException($level, "print", $content, $this->getIndentLevel(), $this->out);
   }
 
   function info($content, ?int $level=null): void {
-    if (!$this->checkLevel($level)) return;
-    $this->printActions();
-    $this->_printGeneric($level, "info", $content, $this->getIndentLevel(), $this->err);
+    $this->_printGenericOrException($level, "info", $content, $this->getIndentLevel(), $this->err);
   }
 
   function note($content, ?int $level=null): void {
-    if (!$this->checkLevel($level)) return;
-    $this->printActions();
-    $this->_printGeneric($level, "note", $content, $this->getIndentLevel(), $this->err);
+    $this->_printGenericOrException($level, "note", $content, $this->getIndentLevel(), $this->err);
   }
 
   function warn($content, ?int $level=null): void {
-    if (!$this->checkLevel($level)) return;
-    $this->printActions();
-    $this->_printGeneric($level, "warn", $content, $this->getIndentLevel(), $this->err);
+    $this->_printGenericOrException($level, "warn", $content, $this->getIndentLevel(), $this->err);
   }
 
   function error($content, ?int $level=null): void {
-    if (!$this->checkLevel($level)) return;
-    $this->printActions();
-    $this->_printGeneric($level, "error", $content, $this->getIndentLevel(), $this->err);
+    $this->_printGenericOrException($level, "error", $content, $this->getIndentLevel(), $this->err);
   }
 
   function end(bool $all=false): void {
diff --git a/tbin/test-console.php b/tbin/test-console.php
index d364f57..248f4b2 100755
--- a/tbin/test-console.php
+++ b/tbin/test-console.php
@@ -2,6 +2,7 @@
 <?php
 require(__DIR__.'/../vendor/autoload.php');
 
+use nulib\UserException;
 use nur\sery\output\std\StdMessenger;
 
 $params = [];
@@ -140,3 +141,19 @@ $c->action("multi-line\naction");
 $c->step("multi-line\nstep");
 $c->adone("multi-line\ndone");
 $c->end(true);
+
+$exception = new Exception("message");
+$userException1 = new UserException("userMessage");
+$userException2 = new UserException("userMessage", "techMessage");
+$c->section("Exceptions");
+$c->title("avec message");
+$c->info(["exception", $exception]);
+$c->info(["userException1", $userException1]);
+$c->info(["userException2", $userException2]);
+$c->end();
+
+$c->title("sans message");
+$c->info($exception);
+$c->info($userException1);
+$c->info($userException2);
+$c->end();