Adds a global try/catch block to handle any exception.

artifacts.php

@@ -169,16 +169,16 @@ function step($conn, $artifactid, $from, $to, $guard, $actions)
         $conn->query("update Artifact set node=$to where ID=$artifactid");
         foreach ($actions as $action) {
             debug("executing $action");
-            try {
+//            try {
                 $action=str_replace("CURRENT_ARTIFACT",$artifactid, $action);
                 if($action=="PIGNISTIC")
                     pignistic($conn,$artifactid);
                 else
                   $conn->query($action);
-            } catch (PDOException $e) {
-                echo "<p>Headache ! <pre>$e</pre></p>";
-                exit;
-            }
+//            } catch (PDOException $e) {
+//                echo "<p>Headache ! <pre>$e</pre></p>";
+//                exit;
+//            }
         }
 
     }

credit.html

@@ -26,11 +26,13 @@
 <h2>Powered by</h2>
 <ul class='creditlist'>
   <li>First-order logic
-  <li>Business artifacts
+  <li>Tuple artifacts
   <li>Bootstrap
   <li>Apache
   <li>PHP
   <li>MySQL
   <li>Python
   <li>Java
+  <li>Javascript</li>
+  <li>Cytoscape.js</li>
 </ul>

index.php

@@ -12,7 +12,6 @@
  *	       MAIN: the main part of the Web page
  */
 
-
 require("HWlib.php");
 require("HTML.php");
 require("profile.php");
@@ -24,9 +23,10 @@ require("show-pages.php");
 require("artifacts.php");
 require("show-artifact.php");
 
-
 session_start();
 
+try { // grobal exception catcher
+
 @debug("Session id: ".$_SESSION['id']);
 @debug("GET parameter: project ".$_GET['project']);
 @debug("Session project: ".$_SESSION['project']);
@@ -202,3 +202,23 @@ if (isset($_SESSION['username'])) {
 
 
 require("template-main.php");
+
+}
+catch (Exception $e){ // global exception handler
+    $message=$e->getMessage();
+    $trace=$e->getTraceAsString();
+    echo "
+        <div class='alert alert-danger' role='alert'>
+        <h1>Headache !</h1>
+        <p>Sorry, we got an internal error. We are on it.</p>
+        <h2>Details</h2>
+        <p>$message</p>
+        <code>";
+     print_r($e->getTrace());
+     echo "
+     </code>
+    </div>";
+    exit;
+}
+
+?>