install: add --with-variant-shortcut configure option

Makefile

@@ -315,6 +315,7 @@ sed -e 's|@prefix@|$(prefix)|g' \
 	-e 's|@availterseoutput@|$(availterseoutput)|g' \
 	-e 's|@listoutput@|$(listoutput)|g' \
 	-e 's|@listterseoutput@|$(listterseoutput)|g' \
+	-e 's|@variantshortcut@|$(variantshortcut)|g' \
 	-e 's|@editor@|$(editor)|g' \
 	-e 's|@autohandling@|$(setautohandling)|g' \
 	-e 's|@implicitrequirement@|$(setimplicitrequirement)|g' \

Makefile.inc.in

@@ -135,6 +135,9 @@ availterseoutput := @availterseoutput@
 listoutput := @listoutput@
 listterseoutput := @listterseoutput@
 
+# variant configuration
+variantshortcut := @variantshortcut@
+
 # editor
 editor := @editor@
 

configure

@@ -38,7 +38,7 @@ pageropts verbosity color darkbgcolors lightbgcolors termbg lockedconfigs \
 icase unloadmatchorder searchmatch modulepath loadedmodules quarantinevars \
 wa277 advversspec ml windowssupport nearlyforbiddendays implicitrequirement \
 tagabbrev tagcolorname mcookieversioncheck availoutput availterseoutput \
-listoutput listterseoutput editor"
+listoutput listterseoutput editor variantshortcut"
 compatarglist=
 libarglist=
 
@@ -130,6 +130,7 @@ availterseoutput='modulepath:alias:dirwsym:sym:tag'
 listoutput='header:idx:variant:sym:tag:key'
 listterseoutput='header'
 editor='vi'
+variantshortcut=
 
 # git branch to use to build compat version
 compatbranch='c-3.2'
@@ -394,6 +395,11 @@ Optional Packages:
                           \`idx', \`variant', \`sym', \`tag' and \`key'
                           (elements in LIST are separated by \`:')
                           [$listterseoutput]
+  --with-variant-shortcut=SHORTCUTLIST
+                          define shortcut characters to specify variant names.
+                          Each element in SHORTCUTLIST is a variant name
+                          associated to a shortcut character (elements in
+                          SHORTCUTLIST are separated by \`:') [$variantshortcut]
   --with-editor=BIN       name or full path of default editor program to use to
                           edit modulefiles [$editor]
   --with-modulepath=PATHLIST
@@ -764,6 +770,8 @@ for arg in "$@"; do
          fi ;
       done ;
       IFS=$ORIG_IFS ;;
+   --with-variant-shortcut=*|--without-variant-shortcut)
+      variantshortcut=$(get_package_value "$arg") ;;
    --with-editor=*|--without-editor)
       editor=$(get_package_value "$arg") ;;
    --with-modulepath=*|--without-modulepath)

site.exp.in

@@ -91,6 +91,8 @@ set install_availterseoutput "@availterseoutput@"
 set install_listoutput "@listoutput@"
 set install_listterseoutput "@listterseoutput@"
 
+set install_variantshortcut "@variantshortcut@"
+
 set install_editor "@editor@"
 
 # command location