From 85aea692359c82ce845464f64a00a2c2ccaab233 Mon Sep 17 00:00:00 2001
From: Jeff Mandell <jeff.mandell@ppfa.org>
Date: Tue, 28 Mar 2017 18:01:50 -0400
Subject: [PATCH] Press b to go back in preview history II

---
 README.md        |  3 ++-
 tools/preview.rb | 10 +++++++++-
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index e0efaf5..679f51c 100644
--- a/README.md
+++ b/README.md
@@ -1042,7 +1042,8 @@ the linked page, it doesn't run on tmux or screen.
 tools/preview.rb schemes/AdventureTime.itermcolors
 
 # Apply the schemes in turn.
-# - Press any key to advance; hit CTRL-C or ESC to stop
+# - Press (almost) any key to advance; hit CTRL-C or ESC to stop
+# - Press the delete key to go back
 tools/preview.rb schemes/*
 ```
 
diff --git a/tools/preview.rb b/tools/preview.rb
index 963b4be..387dc08 100755
--- a/tools/preview.rb
+++ b/tools/preview.rb
@@ -21,6 +21,7 @@ if ENV.has_key? 'TMUX'
 end
 
 preview = files.length > 1
+history = []
 until files.empty?
   file = files.shift
   print "[#{File.basename file, '.*'}] " if preview
@@ -59,7 +60,14 @@ until files.empty?
         'cursor text'   => 'm',
       }.fetch(type, '%x' % type.to_i) << rgb << "\e\\"
     end
-    break if files.empty? || [3.chr, "\e"].include?(IO.console.getch)
+    case IO.console.getch.ord
+    when 127   # backspace
+      files.unshift *[history.pop, file].compact
+    when 3, 27 # ctrl-c, esc
+      break
+    else
+      history << file
+    end
   rescue Exception
     print '(X) '
   end