Index: openacs-4/packages/xowiki/tcl/adp-generator-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xowiki/tcl/adp-generator-procs.tcl,v
diff -u -N -r1.49 -r1.50
--- openacs-4/packages/xowiki/tcl/adp-generator-procs.tcl	21 Oct 2017 16:00:13 -0000	1.49
+++ openacs-4/packages/xowiki/tcl/adp-generator-procs.tcl	24 Dec 2017 12:51:38 -0000	1.50
@@ -107,12 +107,14 @@
     #
     if {![file exists $adpFilename]
         || [file mtime [info script]] > [file mtime $adpFilename]} {
-      if {[catch {set f [open $adpFilename w]} errorMsg]} {
+      try {
+        set f [open $adpFilename w]
+      } on error {errorMsg} {
         :log "Warning: cannot overwrite ADP $adpFilename, ignoring possible changes"
-      } else {
+      } on ok {r} {
         ::puts -nonewline $f [:generate]
         close $f
-        :log "Notice: create ADP $adpFilename"
+        :log "Notice: created ADP $adpFilename"
       }
     }
   }
Index: openacs-4/packages/xowiki/tcl/form-field-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xowiki/tcl/form-field-procs.tcl,v
diff -u -N -r1.254 -r1.255
--- openacs-4/packages/xowiki/tcl/form-field-procs.tcl	21 Dec 2017 20:44:58 -0000	1.254
+++ openacs-4/packages/xowiki/tcl/form-field-procs.tcl	24 Dec 2017 12:51:38 -0000	1.255
@@ -301,7 +301,7 @@
         if {[string match "::xotcl::*" $definition_class] || $method eq ""} {
           error [_ xowiki.error-form_constraint-unknown_attribute [list class [:info class] name ${:name} entry $attribute]]
         }
-        if {[catch {
+        ad_try {
           #
           # We want to allow a programmer to use e.g. options=[xowiki::locales]
           #
@@ -313,7 +313,7 @@
             set value [subst $value]
           }
           my $attribute $value
-        } errMsg]} {
+        } on error {errMsg} {
           error "Error during setting attribute '$attribute' to value '$value': $errMsg"
         }
       }
Index: openacs-4/packages/xowiki/tcl/import-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xowiki/tcl/import-procs.tcl,v
diff -u -N -r1.34 -r1.35
--- openacs-4/packages/xowiki/tcl/import-procs.tcl	22 Dec 2017 13:51:40 -0000	1.34
+++ openacs-4/packages/xowiki/tcl/import-procs.tcl	24 Dec 2017 12:51:38 -0000	1.35
@@ -329,19 +329,20 @@
   exporter proc marshall_all {{-mode export} item_ids} {
     set content ""
     foreach item_id $item_ids {
-      if {[catch {set obj [$item_id marshall -mode $mode]} errorMsg]} {
+      ad_try {
+        set obj [$item_id marshall -mode $mode]
+      } on error {errorMsg} {
         ns_log error "Error while exporting $item_id [$item_id name]\n$errorMsg\n$::errorInfo"
         error $errorMsg
-      } else {
-        append content $obj\n
       }
+      append content $obj\n
     }
     return $content
   }
 
   exporter proc export {item_ids} {
     #
-    # include implictely needed objects, instantiate the objects.
+    # include implicitly needed objects, instantiate the objects.
     #
     set item_ids [:include_needed_objects $item_ids]
     #
@@ -355,7 +356,9 @@
       ns_log notice "--exporting $item_id [$item_id name]"
       set pretty_link [expr {[$item_id package_id] ne "" ? [$item_id pretty_link] : "(not visible)"}]
       ns_write "# exporting $item_id [$item_id name] $pretty_link\n"
-      if {[catch {set obj [$item_id marshall]} errorMsg]} {
+      ad_try {
+        set obj [$item_id marshall]
+      } on error {errorMsg} {
         ns_log error "Error while exporting $item_id [$item_id name]\n$errorMsg\n$::errorInfo"
       } else {
         ns_write "$obj\n" 
Index: openacs-4/packages/xowiki/www/admin/import.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xowiki/www/admin/import.tcl,v
diff -u -N -r1.24 -r1.25
--- openacs-4/packages/xowiki/www/admin/import.tcl	7 Aug 2017 23:48:31 -0000	1.24
+++ openacs-4/packages/xowiki/www/admin/import.tcl	24 Dec 2017 12:51:38 -0000	1.25
@@ -46,32 +46,38 @@
       foreach o [::xowiki::Page allinstances] { 
         set preexists($o) 1
       }
-      if {[catch {namespace eval ::xo::import $content} errorMsg]} {
+      ad_try {
+        namespace eval ::xo::import $content
+      } on error {errorMsg} {
 	ad_log error $errorMsg
 	# cleanup all objects, that did not exist before
         foreach o [::xowiki::Page allinstances] {
 	  if {![info exists preexists($o)]} {
 	    if {[::xotcl::Object isobject $o]} {$o destroy}
 	  }
         }
-      } else {
+      } on ok {r} {
         set objects [list]
         foreach o [::xowiki::Page allinstances] {
           if {![info exists preexists($o)]} {lappend objects $o}
         }
         ns_log notice "objects to import: $objects"
         set parent_id [ns_queryget parent_id 0]
         #::xotcl::Object msg parent_id=$parent_id
-        if {[catch {
+        ad_try {
           set msg [$package_id import -replace $replace -create_user_ids $create_user_ids \
                        -parent_id $parent_id -objects $objects]
-        } errMsg]} {
+        } on error {errMsg} {
           ns_log notice "Error during import: $errMsg\nErrInfo: $::errorInfo"
           ::xotcl::Object msg "Error during import: $errMsg\nErrInfo: $::errorInfo"
           foreach o $objects {$o destroy}
           error $errMsg
         }
-        foreach o $objects {if {[::xotcl::Object isobject $o]} {$o destroy}}
+        foreach o $objects {
+          if {[::xotcl::Object isobject $o]} {
+            $o destroy
+          }
+        }
       }
       namespace delete ::xo::import
     }
Index: openacs-4/packages/xowiki/www/admin/test.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xowiki/www/admin/test.tcl,v
diff -u -N -r1.40 -r1.41
--- openacs-4/packages/xowiki/www/admin/test.tcl	21 Dec 2017 18:09:41 -0000	1.40
+++ openacs-4/packages/xowiki/www/admin/test.tcl	24 Dec 2017 12:51:38 -0000	1.41
@@ -30,8 +30,11 @@
     list [::xo::cc form_parameter $key {}] 
   }
   proc ::ad_returnredirect url {::xo::cc returnredirect $url}
-  if {[catch {set r [uplevel $cmd]} errmsg]} {
-    if {$errmsg ne ""} {test code "error in command: $errmsg [info exists r]"}
+  
+  ad_try {
+    set r [uplevel $cmd]
+  } on error errmsg} {
+    test code "error in command: $errmsg [info exists r]"
     set r ""
   }
   rename ::ns_queryget ""
Index: openacs-4/packages/xowiki/www/portlets/weblog-mini-calendar.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xowiki/www/portlets/weblog-mini-calendar.tcl,v
diff -u -N -r1.19 -r1.20
--- openacs-4/packages/xowiki/www/portlets/weblog-mini-calendar.tcl	7 Aug 2017 23:48:31 -0000	1.19
+++ openacs-4/packages/xowiki/www/portlets/weblog-mini-calendar.tcl	24 Dec 2017 12:51:38 -0000	1.20
@@ -24,9 +24,11 @@
 }
 
 # Get the current month, day, and the first day of the month
-if {[catch {
+ad_try {
   dt_get_info $date
-} errmsg]} {
+} on error {errorMsg} {
+  # if dt_get_info fails from the provided date, try it with the
+  # sysdate.
   set date [dt_sysdate]
   dt_get_info $date
 }