From f08078d68303b87a5c44e093106ee8953edf4dcc Mon Sep 17 00:00:00 2001
From: Christian Brabandt <cb@256bit.org>
Date: Thu, 8 Nov 2018 16:20:37 +0100
Subject: [PATCH] autoload: add comments

---
 autoload/airline.vim | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/autoload/airline.vim b/autoload/airline.vim
index 070e98e2..dce76c90 100644
--- a/autoload/airline.vim
+++ b/autoload/airline.vim
@@ -7,6 +7,11 @@ let g:airline_statusline_funcrefs = get(g:, 'airline_statusline_funcrefs', [])
 
 let s:sections = ['a','b','c','gutter','x','y','z', 'error', 'warning']
 let s:inactive_funcrefs = []
+let s:contexts = {}
+let s:core_funcrefs = [
+      \ function('airline#extensions#apply'),
+      \ function('airline#extensions#default#apply') ]
+
 
 function! airline#add_statusline_func(name)
   call airline#add_statusline_funcref(function(a:name))
@@ -52,6 +57,7 @@ function! airline#load_theme()
   call airline#update_statusline()
 endfunction
 
+" Load an airline theme
 function! airline#switch_theme(name)
   try
     let palette = g:airline#themes#{a:name}#palette "also lazy loads the theme
@@ -74,6 +80,7 @@ function! airline#switch_theme(name)
   call airline#check_mode(winnr())
 endfunction
 
+" Try to load the right theme for the current colorscheme
 function! airline#switch_matching_theme()
   if exists('g:colors_name')
     let existing = g:airline_theme
@@ -99,6 +106,7 @@ function! airline#switch_matching_theme()
   return 0
 endfunction
 
+" Update the statusline
 function! airline#update_statusline()
   if airline#util#getwinvar(winnr(), 'airline_disabled', 0)
     return
@@ -110,11 +118,14 @@ function! airline#update_statusline()
   unlet! w:airline_render_left w:airline_render_right
   exe 'unlet! ' 'w:airline_section_'. join(s:sections, ' w:airline_section_')
 
+  " Now create the active statusline
   let w:airline_active = 1
   let context = { 'winnr': winnr(), 'active': 1, 'bufnr': winbufnr(winnr()) }
   call s:invoke_funcrefs(context, g:airline_statusline_funcrefs)
 endfunction
 
+" Function to be called to make all statuslines inactive
+" Triggered on FocusLost autocommand
 function! airline#update_statusline_focuslost()
   if get(g:, 'airline_focuslost_inactive', 0)
     let bufnr=bufnr('%')
@@ -123,6 +134,8 @@ function! airline#update_statusline_focuslost()
     call airline#update_statusline_inactive(range(1, winnr('$')))
   endif
 endfunction
+
+" Function to draw inactive statuslines for inactive windows
 function! airline#update_statusline_inactive(range)
   if airline#util#getwinvar(winnr(), 'airline_disabled', 0)
     return
@@ -137,10 +150,8 @@ function! airline#update_statusline_inactive(range)
   endfor
 endfunction
 
-let s:contexts = {}
-let s:core_funcrefs = [
-      \ function('airline#extensions#apply'),
-      \ function('airline#extensions#default#apply') ]
+" Gather output from all funcrefs which will later be returned by the
+" airline#statusline() function
 function! s:invoke_funcrefs(context, funcrefs)
   let builder = airline#builder#new(a:context)
   let err = airline#util#exec_funcrefs(a:funcrefs + s:core_funcrefs, builder, a:context)
@@ -151,6 +162,8 @@ function! s:invoke_funcrefs(context, funcrefs)
   endif
 endfunction
 
+" Main statusline function per window
+" will be set to the statusline option
 function! airline#statusline(winnr)
   if has_key(s:contexts, a:winnr)
     return '%{airline#check_mode('.a:winnr.')}'.s:contexts[a:winnr].line
@@ -160,6 +173,7 @@ function! airline#statusline(winnr)
   return ''
 endfunction
 
+" Check if mode as changed
 function! airline#check_mode(winnr)
   if !has_key(s:contexts, a:winnr)
     return ''