Index: openacs-4/packages/acs-tcl/acs-tcl.info
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-tcl/acs-tcl.info,v
diff -u -r1.95.2.37 -r1.95.2.38
--- openacs-4/packages/acs-tcl/acs-tcl.info	5 Jan 2022 14:10:22 -0000	1.95.2.37
+++ openacs-4/packages/acs-tcl/acs-tcl.info	8 Jan 2022 15:37:53 -0000	1.95.2.38
@@ -9,7 +9,7 @@
     <implements-subsite-p>f</implements-subsite-p>
     <inherit-templates-p>t</inherit-templates-p>
 
-    <version name="5.10.1d7" url="http://openacs.org/repository/download/apm/acs-tcl-5.10.1d7.apm">
+    <version name="5.10.1d8" url="http://openacs.org/repository/download/apm/acs-tcl-5.10.1d8.apm">
         <owner url="http://openacs.org">OpenACS</owner>
         <summary>The Kernel Tcl API library.</summary>
         <release-date>2021-09-15</release-date>
@@ -18,7 +18,7 @@
         <license>GPL version 2</license>
         <maturity>3</maturity>
 
-        <provides url="acs-tcl" version="5.10.1d7"/>
+        <provides url="acs-tcl" version="5.10.1d8"/>
         <requires url="acs-bootstrap-installer" version="5.10.0"/>
         <requires url="acs-kernel" version="5.10.1d3"/>
 
Index: openacs-4/packages/acs-tcl/tcl/acs-cache-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-tcl/tcl/acs-cache-procs.tcl,v
diff -u -r1.10.2.24 -r1.10.2.25
--- openacs-4/packages/acs-tcl/tcl/acs-cache-procs.tcl	5 Jan 2022 14:16:48 -0000	1.10.2.24
+++ openacs-4/packages/acs-tcl/tcl/acs-cache-procs.tcl	8 Jan 2022 15:37:54 -0000	1.10.2.25
@@ -431,7 +431,8 @@
 
         :public method eval {
             {-key:required}
-            {-no_empty:switch false}
+            {-no_cache}
+            {-from_cache_indicator}
             cmd
         } {
             #
@@ -441,23 +442,37 @@
             # @param key key for caching, should start with package-key
             #            and a dot to avoid name clashes
             # @param cmd command to be executed.
-            # @return    return the last value set (don't use "return").
+            # @param no_cache list of returned values that should not be cached
+            # @param from_cache_indicator variable name to indicate whether
+            #        the returned value was from cache or not
             #
+            # @return return the last value set (don't use "return").
+            #
             #set cache_key ${:prefix}$key
             #ns_log notice "### exists $cache_key => [dict exists ${:prefix} $key]"
+            if {[info exists from_cache_indicator]} {
+                :upvar $from_cache_indicator from_cache
+            }
 
             if {![info exists ${:prefix}] || ![dict exists [set ${:prefix}] $key]} {
                 #ns_log notice "### call cmd <$cmd>"
+                set from_cache 0
                 set value [:uplevel $cmd]
-                #ns_log notice "### cmd returns <$value> no_empty $no_empty "
-                if {$no_empty && $value eq ""} {
-                    return ""
+                if {[info exists no_cache] && $value in $no_cache} {
+                    #ns_log notice "### cache eval $key returns <$value> without caching"
+                    return $value
                 }
+                #if {$value eq "0"} {
+                #    ns_log notice "### cache eval $key returns <$value> with caching"
+                #}
                 dict set ${:prefix} $key $value
                 #ns_log notice "### [list dict set ${:prefix} $key $value]"
+            } else {
+                set from_cache 1
+                set value [dict get [set ${:prefix}] $key]
             }
             #ns_log notice "### will return [list dict get ${:prefix} $key]"
-            return [dict get [set ${:prefix}] $key]
+            return $value
         }
 
         :public method flush {
Index: openacs-4/packages/acs-tcl/tcl/defs-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-tcl/tcl/defs-procs.tcl,v
diff -u -r1.81.2.14 -r1.81.2.15
--- openacs-4/packages/acs-tcl/tcl/defs-procs.tcl	5 Jan 2022 13:10:51 -0000	1.81.2.14
+++ openacs-4/packages/acs-tcl/tcl/defs-procs.tcl	8 Jan 2022 15:37:54 -0000	1.81.2.15
@@ -515,7 +515,7 @@
         # (without this we see on some sites > 100 locks on this nsv
         # per request).
         #
-        set dict [acs::per_request_cache eval -no_empty -key acs-tcl.ad_param-$key {
+        set dict [acs::per_request_cache eval -no_cache "" -key acs-tcl.ad_param-$key {
             if {[nsv_get ad_param $key result]} {
                 #ns_log notice "ad_parameter_cache $key $parameter_name not cached"
                 set result