style fixes

plugins/dirhistory/dirhistory.plugin.zsh

@@ -49,8 +49,7 @@ function push_future() {
 }
 
 # Called by zsh when directory changes
-typeset -ga chpwd_functions
+chpwd_functions+=(chpwd_dirhistory)
-chpwd_functions+='chpwd_dirhistory'
 function chpwd_dirhistory() {
   push_past $PWD
   # If DIRHISTORY_CD is not set...

plugins/dirpersist/dirpersist.plugin.zsh

@@ -11,8 +11,7 @@ if [[ -f ${dirstack_file} ]] && [[ ${#dirstack[*]} -eq 0 ]] ; then
   [[ -d $dirstack[1] ]] && cd $dirstack[1] && cd $OLDPWD
 fi
 
-typeset -ga chpwd_functions
+chpwd_functions+=(chpwd_dirpersist)
-chpwd_functions+='chpwd_dirpersist'
 chpwd_dirpersist() {
   if (( $DIRSTACKSIZE <= 0 )) || [[ -z $dirstack_file ]]; then return; fi
   local -ax my_stack

plugins/last-working-dir/last-working-dir.plugin.zsh

@@ -8,8 +8,7 @@ mkdir -p $ZSH_CACHE_DIR
 cache_file="$ZSH_CACHE_DIR/last-working-dir"
 
 # Updates the last directory once directory is changed.
-typeset -ga chpwd_functions
+chpwd_functions+=(chpwd_last_working_dir)
-chpwd_functions+='chpwd_last_working_dir'
 function chpwd_last_working_dir() {
   # Use >| in case noclobber is set to avoid "file exists" error
 	pwd >| "$cache_file"