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 -r1.284.2.185 -r1.284.2.186
--- openacs-4/packages/xowiki/tcl/form-field-procs.tcl	4 Jan 2022 17:49:40 -0000	1.284.2.185
+++ openacs-4/packages/xowiki/tcl/form-field-procs.tcl	9 Jan 2022 17:23:26 -0000	1.284.2.186
@@ -114,17 +114,20 @@
     Convert from form_constraint syntax to a dict. This is just a
     partial implementation to be probably extended in the future.  it
     expects that the type is the first element and ignores everything
-    not in the synteax "*=*", or skips "@*" fields. Don't expect this
+    not in the syntax "*=*", or skips "@*" fields. Don't expect this
     to be fully reversible.
 
   } {
     set result ""
     foreach fc $form_constraints {
       #ns_log notice "... fc_to_dict works on <$fc>"
-      if {[regexp {^([^:]+):(.*)$} $fc _ field_name definition]} {
+      set p [string first : $fc]
+      if {$p > -1} {
+        set field_name [string range $fc 0 $p-1]
+        set short_spec [string range $fc $p+1 end]
         if {[string match @* $field_name]} continue
-        dict set result $field_name [spec_to_dict -name $field_name $definition]
-        dict set result $field_name _definition $definition
+        dict set result $field_name [spec_to_dict -name $field_name $short_spec]
+        dict set result $field_name _definition $short_spec
       }
     }
     return $result
Index: openacs-4/packages/xowiki/tcl/xowiki-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xowiki/tcl/xowiki-procs.tcl,v
diff -u -r1.542.2.130 -r1.542.2.131
--- openacs-4/packages/xowiki/tcl/xowiki-procs.tcl	2 Jan 2022 18:13:12 -0000	1.542.2.130
+++ openacs-4/packages/xowiki/tcl/xowiki-procs.tcl	9 Jan 2022 17:23:26 -0000	1.542.2.131
@@ -2389,11 +2389,16 @@
     @return the pretty_link for the current page
     @see ::xowiki::Package instproc pretty_link
   } {
+    if {${:parent_id} eq "0"} {
+      set msg "you must not call pretty_link on a page with parent_id 0"
+      ad_log error $msg
+      error $msg
+    }
     ${:package_id} pretty_link -parent_id ${:parent_id} \
         -anchor $anchor -query $query -absolute $absolute -siteurl $siteurl \
         -lang $lang -download $download -page [self] \
         -path_encode $path_encode \
-        ${:name} \
+        ${:name}
   }
 
   Page instproc detail_link {} {
@@ -3176,6 +3181,23 @@
     return $content
   }
 
+  Page instproc content_header_append {text} {
+    #
+    # This function is to be called on pages that want to prepend
+    # content prior to the main content. This is especially important
+    # for HTML forms (e.g. produced by the xowiki::Form renderer),
+    # where the form-body is not allowed to contain nested forms.
+    #
+    append ::__xowiki__content_header $text \n
+  }
+  
+  Page instproc content_header_get {} {
+    if {[info exists ::__xowiki__content_header]} {
+      return $::__xowiki__content_header
+    }
+  }
+
+  
   Page instproc form_field_index {form_field_objs} {
     set marker ::__computed_form_field_names($form_field_objs)
     if {[info exists $marker]} return
@@ -3392,7 +3414,7 @@
       if {![nsf::is object $context]} {
         ::xo::ConnectionContext require \
             -package_id $package_id \
-            -url [:pretty_link]
+            -url [::$package_id pretty_link ${:name}]
       }
       set creation_user [$context user_id]
     }
@@ -4013,9 +4035,10 @@
     # OpenACS 5.10: In case we have a folder instances without the
     # "description" field set, and we use the new folder.form, and the
     # update script was not yet executed, folders might appear as
-    # empty. In htese cases, call child-resosurces manually.
+    # empty. In these cases, call child-resources manually.
     #
     if {$html eq "" && [:is_folder_page]} {
+      ns_log warning "render_content: [:item_id] {$name} is a folder page without a content (deprecated)"
       set html [:include child-resources]
     }
 
@@ -4174,7 +4197,7 @@
       set html ""; set mime ""
       lassign ${:text} html mime
       set content [:substitute_markup $html]
-    } elseif {[lindex ${:form} 0] ne ""} {
+    } elseif {[lindex ${:form} 0] ne ""} {      
       set content [[self class] disable_input_fields [lindex ${:form} 0]]
     } else {
       set content ""
@@ -4187,7 +4210,39 @@
     return [:form_constraints]
   }
 
-
+  FormPage instproc create_form_fields_from_names {
+    {-lookup:switch}
+    {-set_values:switch}
+    {-form_constraints}
+    field_names
+  } {
+    #
+    # Create form-fields from field names. When "-lookup" is
+    # specified, the code tries to reuseexisting form-field instead of
+    # creating/recreating it.
+    #
+    # Since create_raw_form_field uses destroy_on_cleanup, we do not
+    # have to care here about destroying the objects.
+    #
+    set form_fields {}
+    foreach field_name $field_names {
+      if {$lookup && [:form_field_exists $field_name]} {
+        #:msg "... found form_field for $field_name"
+        lappend form_fields [:lookup_form_field -name $field_name {}]
+      } else {
+        #:msg "create '$spec_name' with spec '$short_spec'"
+        lappend form_fields [:create_raw_form_field \
+                                 -name $field_name \
+                                 -form_constraints $form_constraints \
+                                ]
+      }
+    }
+    if {$set_values} {
+      :load_values_into_form_fields $form_fields      
+    }
+    return $form_fields
+  }
+  
   Page instproc create_form_fields_from_form_constraints {
     {-lookup:switch}
     form_constraints
@@ -4214,7 +4269,9 @@
         lappend form_fields [:create_raw_form_field \
                                  -name $spec_name \
                                  -slot [:find_slot $spec_name] \
-                                 -spec $short_spec]
+                                 -spec $short_spec \
+                                 -form_constraints $form_constraints \
+                                ]
       }
     }
     return $form_fields
@@ -5098,13 +5155,11 @@
     #
     # Produce an HTML rendering from the FormPage.
     #
-
     #set package_id ${:package_id}
     :include_header_info -prefix form_view
     if {[::xo::cc mobile]} {
       :include_header_info -prefix mobile
     }
-
     set text [:get_from_template text]
     if {$text ne ""} {
       catch {set text [lindex $text 0]}
@@ -5165,7 +5220,6 @@
     return $HTML
   }
 
-
   FormPage instproc get_value {{-field_spec ""} {-cr_field_spec ""} before varname} {
     #
     # Read a property (instance attribute) and return
Index: openacs-4/packages/xowiki/tcl/xowiki-www-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/xowiki/tcl/xowiki-www-procs.tcl,v
diff -u -r1.368.2.105 -r1.368.2.106
--- openacs-4/packages/xowiki/tcl/xowiki-www-procs.tcl	2 Jan 2022 16:15:02 -0000	1.368.2.105
+++ openacs-4/packages/xowiki/tcl/xowiki-www-procs.tcl	9 Jan 2022 17:23:26 -0000	1.368.2.106
@@ -1912,8 +1912,10 @@
     # make use of the same templating machinery below.
     #
     if {$content eq ""} {
-      set content [:render]
+      set content [:content_header_get][:render]
       #:msg "--after render"
+    } else {
+      set content [:content_header_get]$content
     }
 
     #
@@ -2265,6 +2267,7 @@
     {-configuration ""}
     {-omit_field_name_spec:boolean false}
     {-nls_language ""}
+    {-form_constraints ""}
   } {
     #ns_log notice "... create_raw_form_field name $name spec '$spec'"
     set save_slot $slot
@@ -2323,6 +2326,7 @@
     {-configuration ""}
     {-omit_field_name_spec:boolean false}
     {-nls_language ""}
+    {-form_constraints ""}
   } {
     #
     # For workflows, we do not want to get the form constraints of the
@@ -2341,7 +2345,7 @@
       # Get for the current page (self) the form-constraints and
       # return the spec for the specifiled name.
       #
-      set short_spec [:get_short_spec $name]
+      set short_spec [:get_short_spec -form_constraints $form_constraints $name]
       #:log "$name get_short_spec returns <$short_spec>"
     }
 
@@ -2525,7 +2529,16 @@
   }
 
   FormPage ad_instproc set_form_data {form_fields} {
-    Store the instance attributes or default values in the form.
+
+    Store the instance attributes or default values into the form via
+    set_form_value. This function iterates over the provided
+    form-fields and checks, if these are known fields in the current
+    form. These known field names are defined via the method
+    "field_names" that extracts these names from a form.
+
+    If one wants to load all values from an FormPage into the provided
+    form-fields, use method "load_values_into_form_fields" instead.
+
   } {
     ::xo::require_html_procs
 
@@ -2594,8 +2607,8 @@
     #:msg "fields $field_names // $form_fields"
     #foreach f $form_fields { :msg "... $f [$f name]" }
     #
-    # We have a form and get all form input from the fields of the
-    # from into form field objects.
+    # We have the form data and get all form_parameters into the
+    # form-field objects.
     #
     foreach att $field_names {
       #:msg "getting att=$att"
@@ -2885,6 +2898,7 @@
   }
 
   FormPage instproc field_names {{-form ""}} {
+    #ns_log notice "=== field_names form <$form>"
     #
     # Ge the field-names mentioned in form (the provided form has
     # always highest precedence).
@@ -2993,7 +3007,13 @@
   }
 
 
-  FormPage instproc load_values_into_form_fields {form_fields} {
+  FormPage ad_instproc load_values_into_form_fields {form_fields} {
+
+    Load either the instance variables or the instance attributes into
+    the provided form-fields. The function sets the values based on
+    the default values and the values for the current object.
+
+  } {
     set is_new [:is_new_entry ${:name}]
 
     foreach f $form_fields {