--- loncom/xml/run.pm	2000/06/28 13:01:52	1.1
+++ loncom/xml/run.pm	2000/10/11 13:33:33	1.8
@@ -1,9 +1,39 @@
-        sub evaluate {
-	    my ($expression,$safeeval) = @_;
-            return $safeeval->reval($expression);
-        }
+package Apache::run;
 
-        sub run {
-	    my ($code,$safeeval) = @_;
-            $safeeval->reval($code);
-        }
+sub evaluate {
+  my ($expression,$safeeval,$decls) = @_;
+# print "inside2 evaluate $decls with $expression<br>\n";
+# gerd's old method interpolates unset vars
+# $safeeval->reval('return qq('.$expression.');');
+  unless (defined $expression) { return ''; }
+  my $result = '';
+  $@='';
+  $safeeval->reval('$_=q{'.$expression.'};');
+  if ($@ eq '') {
+    $safeeval->reval('{'.$decls.'$_=~s/(\$\{?[A-Za-z]\w*\}?)/(defined(eval($1))?eval($1):$1)/ge;}');
+    if ($@ eq '') {
+      $result = $safeeval->reval('return $_;');
+    } else {
+      &Apache::lonxml::error("substituion on:$expression:with:$decls:caused");
+    }
+  } else {
+    &Apache::lonxml::error("defining:$expression:caused");
+  }
+  if ($@ ne '') {&Apache::lonxml::error($@);}
+  return $result
+}
+
+sub run {
+  my ($code,$safeeval) = @_;
+#  print "inside run\n";
+  $@='';
+  my $result=$safeeval->reval($code);
+  if ($@ ne '') { 
+    &Apache::lonxml::error(":$code:caused"); 
+    &Apache::lonxml::error($@); 
+  }
+  return $result;
+}
+
+1;
+__END__;