diff --git a/autoload/airline/extensions/tabline/builder.vim b/autoload/airline/extensions/tabline/builder.vim
index 1a53cac..d6823c2 100644
--- a/autoload/airline/extensions/tabline/builder.vim
+++ b/autoload/airline/extensions/tabline/builder.vim
@@ -15,10 +15,10 @@ function! s:prototype.build() dict
     let tab_nr_type = get(g:, 'airline#extensions#tabline#tab_nr_type', 0)
     let num_tabs = tabpagenr('$')
     let curtab = self._curtab
-    let left_tab = curtab - 1
-    let right_tab = curtab + 1
-    let left_position = self._tabs_position
-    let right_position = self._tabs_position + 1
+    let self._left_tab = curtab - 1
+    let self._right_tab = curtab + 1
+    let self._left_position = self._tabs_position
+    let self._right_position = self._tabs_position + 1
     let remaining_space = &columns - s:strchars(s:evaluate_tabline(self._build()))
 
     let left_sep_size = s:strchars(s:evaluate_tabline(self._context.left_sep))
@@ -35,54 +35,54 @@ function! s:prototype.build() dict
     " There are always two left_seps (either side of the selected tab) and all
     " other seperators are left_alt_seps.
     let remaining_space -= 2 * left_sep_size - left_alt_sep_size
-    call self.insert_section(self.get_group(curtab), tab_title, left_position)
+    call self.insert_section(self.get_group(curtab), tab_title, self._left_position)
 
     if get(g:, 'airline#extensions#tabline#current_first', 0)
       " always have current tabpage first
-      let left_position += 1
+      let self._left_position += 1
     endif
 
     " Add the tab to the right
-    if right_tab <= num_tabs
-      let tab_title = self.get_title(tab_nr_type, right_tab)
+    if self._right_tab <= num_tabs
+      let tab_title = self.get_title(tab_nr_type, self._right_tab)
       let remaining_space -= s:strchars(s:evaluate_tabline(tab_title)) + left_alt_sep_size
-      call self.insert_section(self.get_group(right_tab), tab_title, right_position)
-      let right_position += 1
-      let right_tab += 1
+      call self.insert_section(self.get_group(self._right_tab), tab_title, self._right_position)
+      let self._right_position += 1
+      let self._right_tab += 1
     endif
 
     while remaining_space > 0
-      if left_tab > 0
-        let tab_title = self.get_title(tab_nr_type, left_tab)
+      if self._left_tab > 0
+        let tab_title = self.get_title(tab_nr_type, self._left_tab)
         let remaining_space -= s:strchars(s:evaluate_tabline(tab_title)) + left_alt_sep_size
         if remaining_space >= 0
-          call self.insert_section(self.get_group(left_tab), tab_title, left_position)
-          let right_position += 1
-          let left_tab -= 1
+          call self.insert_section(self.get_group(self._left_tab), tab_title, self._left_position)
+          let self._right_position += 1
+          let self._left_tab -= 1
         endif
-      elseif right_tab <= num_tabs
-        let tab_title = self.get_title(tab_nr_type, right_tab)
+      elseif self._right_tab <= num_tabs
+        let tab_title = self.get_title(tab_nr_type, self._right_tab)
         let remaining_space -= s:strchars(s:evaluate_tabline(tab_title)) + left_alt_sep_size
         if remaining_space >= 0
-          call self.insert_section(self.get_group(right_tab), tab_title, right_position)
-          let right_position += 1
-          let right_tab += 1
+          call self.insert_section(self.get_group(self._right_tab), tab_title, self._right_position)
+          let self._right_position += 1
+          let self._right_tab += 1
         endif
       else
         break
       endif
     endwhile
 
-    if left_tab > 0
+    if self._left_tab > 0
       if get(g:, 'airline#extensions#tabline#current_first', 0)
-        let left_position -= 1
+        let self._left_position -= 1
       endif
-      call self.insert_raw('%#airline_tab#'.skipped_tabs_marker, left_position)
-      let right_position += 1
+      call self.insert_raw('%#airline_tab#'.skipped_tabs_marker, self._left_position)
+      let self._right_position += 1
     endif
 
-    if right_tab <= num_tabs
-      call self.insert_raw('%#airline_tab#'.skipped_tabs_marker, right_position)
+    if self._right_tab <= num_tabs
+      call self.insert_raw('%#airline_tab#'.skipped_tabs_marker, self._right_position)
     endif
   endif