install: add --with-sticky-purge configure option

Introduce the --with-sticky-purge configure option to choose at
installation time the default error behavior when unloading a sticky
module during a purge command. Allowed values are error (default),
warning and silent.

Makefile

@@ -401,6 +401,7 @@ sed -e 's|@prefix@|$(prefix)|g' \
 	-e 's|@nearlyforbiddendays@|$(nearlyforbiddendays)|g' \
 	-e 's|@tagabbrev@|$(tagabbrev)|g' \
 	-e 's|@tagcolorname@|$(tagcolorname)|g' \
+	-e 's|@stickypurge@|$(stickypurge)|g' \
 	-e 's|@availoutput@|$(availoutput)|g' \
 	-e 's|@availterseoutput@|$(availterseoutput)|g' \
 	-e 's|@listoutput@|$(listoutput)|g' \

Makefile.inc.in

@@ -121,6 +121,9 @@ nearlyforbiddendays := @nearlyforbiddendays@
 tagabbrev := @tagabbrev@
 tagcolorname := @tagcolorname@
 
+# error behavior when purging sticky module
+stickypurge := @stickypurge@
+
 # check version on magic cookie
 mcookieversioncheck := @mcookieversioncheck@
 

configure

@@ -38,7 +38,8 @@ searchmatch modulepath loadedmodules quarantinevars wa277 advversspec ml \
 windowssupport nearlyforbiddendays implicitrequirement tagabbrev \
 tagcolorname mcookieversioncheck availoutput availterseoutput listoutput \
 listterseoutput editor variantshortcut bashcompletiondir fishcompletiondir \
-zshcompletiondir tcllinter tcllinteropts nagelfardatadir nagelfaraddons"
+zshcompletiondir tcllinter tcllinteropts nagelfardatadir nagelfaraddons \
+stickypurge"
 libarglist=()
 
 # flags to know if argument has been specified on command-line
@@ -116,6 +117,7 @@ windowssupport=n
 nearlyforbiddendays=14
 tagabbrev='auto-loaded=aL:loaded=L:hidden=H:hidden-loaded=H:forbidden=F:nearly-forbidden=nF:sticky=S:super-sticky=sS:keep-loaded=kL'
 tagcolorname=
+stickypurge=error
 mcookieversioncheck=y
 availoutput='modulepath:alias:dirwsym:sym:tag:variantifspec:key'
 availterseoutput='modulepath:alias:dirwsym:sym:tag:variantifspec'
@@ -368,6 +370,11 @@ Optional Packages:
                           the module they are attached to. Each element in
                           TAGLIST is a tag name or abbreviation (elements in
                           TAGLIST are separated by \`:') [$tagcolorname]
+  --with-sticky-purge=VALUE
+                          define the kind of error to render when unloading
+                          a sticky or super-sticky module during a purge.
+                          Raise an \`error' or report a \`warning' or be
+                          \`silent'. [$stickypurge]
   --with-avail-output=LIST
                           specify content to report on avail sub-command
                           regular output. elements accepted in LIST are:
@@ -747,6 +754,13 @@ for arg in "$@"; do
       tagabbrev=$(get_package_value "$arg") ;;
    --with-tag-color-name*|--without-tag-color-name)
       tagcolorname=$(get_package_value "$arg") ;;
+   --with-sticky-purge*|--without-sticky-purge)
+      stickypurge=$(get_package_value "$arg" "error") ;
+      allowedval=" error warning silent " ;
+      if [ "${allowedval// $stickypurge /}" = "$allowedval" ]; then
+         echo_error "Bad value for option \`--with-sticky-purge'"\
+            "Allowed values are:$allowedval"
+      fi ;;
    --with-avail-output*|--without-avail-output)
       availoutput=$(get_package_value "$arg" "$availoutput") ;
       allowedval=" modulepath alias dirwsym indesym sym tag key variant variantifspec " ;

site.exp.in

@@ -85,6 +85,8 @@ set install_nearlyforbiddendays "@nearlyforbiddendays@"
 set install_tagabbrev "@tagabbrev@"
 set install_tagcolorname "@tagcolorname@"
 
+set install_stickypurge "@stickypurge@"
+
 set install_mcookieversioncheck "@mcookieversioncheck@"
 
 set install_availoutput "@availoutput@"

tcl/init.tcl.in

@@ -118,7 +118,8 @@ array set g_config_defs [list\
    silent_shell_debug {MODULES_SILENT_SHELL_DEBUG @silentshdbgsupport@ 0 b {0\
       1}}\
    siteconfig {{} {@etcdir@/siteconfig.tcl} 0 s}\
-   sticky_purge {MODULES_STICKY_PURGE error 0 s {error warning silent}}\
+   sticky_purge {MODULES_STICKY_PURGE {@stickypurge@} 0 s {error warning\
+      silent}}\
    tag_abbrev {MODULES_TAG_ABBREV {@tagabbrev@} 0 l {} {} initConfTagAbbrev}\
    tag_color_name {MODULES_TAG_COLOR_NAME {@tagcolorname@} 0 l {} {}\
       initConfTagColorName}\