diff --git a/README.md b/README.md
index 5f501cd..4b0a2b4 100644
--- a/README.md
+++ b/README.md
@@ -521,7 +521,7 @@ Oops! We forgot the cool mark for the branch component! (work with the patched f
 function! LightLineFugitive()
   if exists("*fugitive#head")
     let _ = fugitive#head()
-    return strlen(_) ? '⭠ '._ : ''
+    return _ !=# '' ? '⭠ '._ : ''
   endif
   return ''
 endfunction
@@ -597,7 +597,7 @@ endfunction
 function! LightLineFugitive()
   if &ft !~? 'vimfiler\|gundo' && exists("*fugitive#head")
     let _ = fugitive#head()
-    return strlen(_) ? '⭠ '._ : ''
+    return _ !=# '' ? '⭠ '._ : ''
   endif
   return ''
 endfunction
@@ -607,11 +607,11 @@ function! LightLineFileformat()
 endfunction
 
 function! LightLineFiletype()
-  return winwidth(0) > 70 ? (strlen(&filetype) ? &filetype : 'no ft') : ''
+  return winwidth(0) > 70 ? (&filetype !=# '' ? &filetype : 'no ft') : ''
 endfunction
 
 function! LightLineFileencoding()
-  return winwidth(0) > 70 ? (strlen(&fenc) ? &fenc : &enc) : ''
+  return winwidth(0) > 70 ? (&fenc !=# '' ? &fenc : &enc) : ''
 endfunction
 
 function! LightLineMode()
@@ -692,7 +692,7 @@ function! LightLineFugitive()
     if expand('%:t') !~? 'Tagbar\|Gundo\|NERD' && &ft !~? 'vimfiler' && exists('*fugitive#head')
       let mark = ''  " edit here for cool mark
       let _ = fugitive#head()
-      return strlen(_) ? mark._ : ''
+      return _ !=# '' ? mark._ : ''
     endif
   catch
   endtry
@@ -704,11 +704,11 @@ function! LightLineFileformat()
 endfunction
 
 function! LightLineFiletype()
-  return winwidth(0) > 70 ? (strlen(&filetype) ? &filetype : 'no ft') : ''
+  return winwidth(0) > 70 ? (&filetype !=# '' ? &filetype : 'no ft') : ''
 endfunction
 
 function! LightLineFileencoding()
-  return winwidth(0) > 70 ? (strlen(&fenc) ? &fenc : &enc) : ''
+  return winwidth(0) > 70 ? (&fenc !=# '' ? &fenc : &enc) : ''
 endfunction
 
 function! LightLineMode()
diff --git a/autoload/lightline/tab.vim b/autoload/lightline/tab.vim
index ca30f7c..f2accc1 100644
--- a/autoload/lightline/tab.vim
+++ b/autoload/lightline/tab.vim
@@ -2,7 +2,7 @@
 " Filename: autoload/lightline/tab.vim
 " Author: itchyny
 " License: MIT License
-" Last Change: 2015/01/04 22:44:42.
+" Last Change: 2016/05/07 22:31:02.
 " =============================================================================
 
 let s:save_cpo = &cpo
@@ -12,7 +12,7 @@ function! lightline#tab#filename(n) abort
   let buflist = tabpagebuflist(a:n)
   let winnr = tabpagewinnr(a:n)
   let _ = expand('#'.buflist[winnr - 1].':t')
-  return strlen(_) ? _ : '[No Name]'
+  return _ !=# '' ? _ : '[No Name]'
 endfunction
 
 function! lightline#tab#modified(n) abort
diff --git a/doc/lightline.txt b/doc/lightline.txt
index 45eec4e..541e23c 100644
--- a/doc/lightline.txt
+++ b/doc/lightline.txt
@@ -287,7 +287,7 @@ nice.
 	function! LightLineFugitive()
 		if exists('*fugitive#head')
 			let _ = fugitive#head()
-			return strlen(_) ? ''._ : ''
+			return _ !=# '' ? ''._ : ''
 		endif
 		return ''
 	endfunction
@@ -312,7 +312,7 @@ look nice.
 	function! LightLineFugitive()
 		if exists('*fugitive#head')
 			let _ = fugitive#head()
-			return strlen(_) ? '⭠ '._ : ''
+			return _ !=# '' ? '⭠ '._ : ''
 		endif
 		return ''
 	endfunction
@@ -742,7 +742,7 @@ A nice example for |vim-powerline| font users:
 	function! LightLineFugitive()
 		if &ft !~? 'vimfiler' && exists('*fugitive#head')
 			let _ = fugitive#head()
-			return strlen(_) ? '⭠ '._ : ''
+			return _ !=# '' ? '⭠ '._ : ''
 		endif
 		return ''
 	endfunction
@@ -803,7 +803,7 @@ For users who uses lots of plugins:
 	    if expand('%:t') !~? 'Tagbar\|Gundo\|NERD' && &ft !~? 'vimfiler' && exists('*fugitive#head')
 	      let mark = ''  " edit here for cool mark
 	      let _ = fugitive#head()
-	      return strlen(_) ? mark._ : ''
+	      return _ !=# '' ? mark._ : ''
 	    endif
 	  catch
 	  endtry
@@ -815,11 +815,11 @@ For users who uses lots of plugins:
 	endfunction
 
 	function! LightLineFiletype()
-	  return winwidth(0) > 70 ? (strlen(&filetype) ? &filetype : 'no ft') : ''
+	  return winwidth(0) > 70 ? (&filetype !=# '' ? &filetype : 'no ft') : ''
 	endfunction
 
 	function! LightLineFileencoding()
-	  return winwidth(0) > 70 ? (strlen(&fenc) ? &fenc : &enc) : ''
+	  return winwidth(0) > 70 ? (&fenc !=# '' ? &fenc : &enc) : ''
 	endfunction
 
 	function! LightLineMode()