diff --git a/fzf b/fzf
index 241d597..d4228b3 100755
--- a/fzf
+++ b/fzf
@@ -174,7 +174,8 @@ class FZF
 
   Environment variables
     FZF_DEFAULT_COMMAND  Default command to use when input is tty
-    FZF_DEFAULT_OPTS     Defaults options. (e.g. "-x -m --sort 10000")] + $/ + $/
+    FZF_DEFAULT_OPTS     Defaults options. (e.g. "-x -m --sort 10000")
+    FZF_MOUSE_ENABLED    Set to 0 to disable mouse] + $/ + $/
     exit x
   end
 
@@ -471,7 +472,7 @@ class FZF
 
   def init_screen
     C.init_screen
-    if ENV.fetch('FZF_MOUSE_ENABLED', '1') == '1'
+    unless ENV.fetch('FZF_MOUSE_ENABLED', '1') == '0'
       C.mouseinterval 0
       C.mousemask C::ALL_MOUSE_EVENTS
     end
@@ -715,6 +716,10 @@ class FZF
     end
   end
 
+  def test_mouse st, *states
+    states.any? { |s| s & st > 0 }
+  end
+
   def start_loop
     got = nil
     begin
@@ -765,13 +770,13 @@ class FZF
           nil
         },
       }
-      actions[C::KEY_LEFT]  = actions[ctrl(:b)]
-      actions[C::KEY_RIGHT] = actions[ctrl(:f)]
-      actions[127]          = actions[ctrl(:h)]
-      actions[C::KEY_DOWN]  = actions[ctrl(:n)]    = actions[ctrl(:j)]
-      actions[C::KEY_UP]    = actions[ctrl(:p)]    = actions[ctrl(:k)]
-      actions[ctrl(:q)]     = actions[ctrl(:g)]    = actions[ctrl(:c)] = actions[:esc]
-      actions[:select]      = actions[C::KEY_BTAB] = actions[ctrl(:i)]
+      actions[C::KEY_UP]        = actions[ctrl(:p)] = actions[ctrl(:k)]
+      actions[C::KEY_DOWN]      = actions[ctrl(:n)] = actions[ctrl(:j)]
+      actions[C::KEY_LEFT]      = actions[ctrl(:b)]
+      actions[C::KEY_RIGHT]     = actions[ctrl(:f)]
+      actions[C::KEY_BTAB]      = actions[:select]  = actions[ctrl(:i)]
+      actions[C::KEY_BACKSPACE] = actions[127]      = actions[ctrl(:h)]
+      actions[ctrl(:q)] = actions[ctrl(:g)] = actions[ctrl(:c)] = actions[:esc]
 
       emit(:key) { [@query.get, cursor] } unless @query.empty?
       pmv = nil
@@ -786,15 +791,15 @@ class FZF
         when C::KEY_MOUSE
           if m = C.getmouse
             st = m.bstate
-            if ((st & C::BUTTON1_PRESSED) | (st & C::BUTTON1_RELEASED)) > 0
+            if test_mouse(st, C::BUTTON1_PRESSED, C::BUTTON1_RELEASED)
               if m.y == cursor_y
                 # TODO Wide-characters
                 cursor = [0, [input.length, m.x - 2].min].max
               elsif m.x > 1 && m.y <= max_items
                 vselect { |v|
                   tv = max_items - m.y - 1
-                  if st & C::BUTTON1_RELEASED > 0
-                    if (st & C::BUTTON_SHIFT) > 0
+                  if test_mouse(st, C::BUTTON1_RELEASED)
+                    if test_mouse(st, C::BUTTON_SHIFT)
                       ch = :select
                     elsif pmv == tv
                       ch = ctrl(:m)
@@ -804,9 +809,9 @@ class FZF
                   tv
                 }
               end
-            elsif ((st & 0x8000000) | (st & C::BUTTON2_PRESSED)) > 0
+            elsif test_mouse(st, 0x8000000, C::BUTTON2_PRESSED)
               ch = C::KEY_DOWN
-            elsif (st & C::BUTTON4_PRESSED) > 0
+            elsif test_mouse(st, C::BUTTON4_PRESSED)
               ch = C::KEY_UP
             end
           end
@@ -820,26 +825,25 @@ class FZF
             else
               ch2
             end
-        when Fixnum
-          # Ruby 1.8
-          if (ch.chr rescue nil) && ch.chr =~ /[[:print:]]/
-            ch = ch.chr
-          else
-            chs = [ch]
-            (num_unicode_bytes(ch) - 1).times do |i|
-              chs << C.getch
-            end
+        end
 
-            # UTF-8 TODO Ruby 1.8
-            if chs.length > 1
+        upd = actions.fetch(ch, proc { |ch|
+          if ch.is_a?(Fixnum)
+            # Ruby 1.8
+            if (ch.chr rescue '') =~ /[[:print:]]/
+              ch = ch.chr
+            elsif (nch = num_unicode_bytes(ch)) > 1
+              chs = [ch]
+              (nch - 1).times do |i|
+                chs << C.getch
+              end
+              # UTF-8 TODO Ruby 1.8
               ch = chs.pack('C*').force_encoding('UTF-8')
             end
           end
-        end
 
-        upd = actions.fetch(ch, proc { |chr|
-          if chr =~ /[[:print:]]/
-            input.insert cursor, chr
+          if ch.is_a?(String) && ch =~ /[[:print:]]/
+            input.insert cursor, ch
             cursor += 1
           end
         }).call(ch)