diff --git a/keyboard.zsh b/keyboard.zsh
index 590ab7c..cb583b0 100644
--- a/keyboard.zsh
+++ b/keyboard.zsh
@@ -24,57 +24,57 @@ keyinfo=(
   'Control'   '\C-'
   'Escape'    '\e'
   'Meta'      '\M-'
-  'F1'        "${terminfo[kf1]}"
-  'F2'        "${terminfo[kf2]}"
-  'F3'        "${terminfo[kf3]}"
-  'F4'        "${terminfo[kf4]}"
-  'F5'        "${terminfo[kf5]}"
-  'F6'        "${terminfo[kf6]}"
-  'F7'        "${terminfo[kf7]}"
-  'F8'        "${terminfo[kf8]}"
-  'F9'        "${terminfo[kf9]}"
-  'F10'       "${terminfo[kf10]}"
-  'F11'       "${terminfo[kf11]}"
-  'F12'       "${terminfo[kf12]}"
-  'Backspace' "${terminfo[kbs]}"
-  'Insert'    "${terminfo[kich1]}"
-  'Home'      "${terminfo[khome]}"
-  'PageUp'    "${terminfo[kpp]}"
-  'Delete'    "${terminfo[kdch1]}"
-  'End'       "${terminfo[kend]}"
-  'PageDown'  "${terminfo[knp]}"
-  'Up'        "${terminfo[kcuu1]}"
-  'Left'      "${terminfo[kcub1]}"
-  'Down'      "${terminfo[kcud1]}"
-  'Right'     "${terminfo[kcuf1]}"
-  'BackTab'   "${terminfo[kcbt]}"
+  'F1'        "$terminfo[kf1]"
+  'F2'        "$terminfo[kf2]"
+  'F3'        "$terminfo[kf3]"
+  'F4'        "$terminfo[kf4]"
+  'F5'        "$terminfo[kf5]"
+  'F6'        "$terminfo[kf6]"
+  'F7'        "$terminfo[kf7]"
+  'F8'        "$terminfo[kf8]"
+  'F9'        "$terminfo[kf9]"
+  'F10'       "$terminfo[kf10]"
+  'F11'       "$terminfo[kf11]"
+  'F12'       "$terminfo[kf12]"
+  'Backspace' "$terminfo[kbs]"
+  'Insert'    "$terminfo[kich1]"
+  'Home'      "$terminfo[khome]"
+  'PageUp'    "$terminfo[kpp]"
+  'Delete'    "$terminfo[kdch1]"
+  'End'       "$terminfo[kend]"
+  'PageDown'  "$terminfo[knp]"
+  'Up'        "$terminfo[kcuu1]"
+  'Left'      "$terminfo[kcub1]"
+  'Down'      "$terminfo[kcud1]"
+  'Right'     "$terminfo[kcuf1]"
+  'BackTab'   "$terminfo[kcbt]"
 )
 
 if [[ "$KEYMAP" == (emacs|) ]]; then
   # Use Emacs key bindings.
   bindkey -e
 
-  bindkey "${keyinfo[Escape]}b" emacs-backward-word
-  bindkey "${keyinfo[Escape]}f" emacs-forward-word
-  bindkey "${keyinfo[Escape]}${keyinfo[Left]}" emacs-backward-word
-  bindkey "${keyinfo[Escape]}${keyinfo[Right]}" emacs-forward-word
+  bindkey "$keyinfo[Escape]b" emacs-backward-word
+  bindkey "$keyinfo[Escape]f" emacs-forward-word
+  bindkey "$keyinfo[Escape]$keyinfo[Left]" emacs-backward-word
+  bindkey "$keyinfo[Escape]$keyinfo[Right]" emacs-forward-word
 
   # Kill to the beginning of the line.
-  bindkey "${keyinfo[Control]}u" backward-kill-line
+  bindkey "$keyinfo[Control]u" backward-kill-line
 
   # Kill to the beginning of the word.
-  bindkey "${keyinfo[Control]}w" backward-kill-word
+  bindkey "$keyinfo[Control]w" backward-kill-word
 
   # Undo/Redo
-  bindkey "${keyinfo[Control]}_" undo
-  bindkey "${keyinfo[Escape]}_" redo
+  bindkey "$keyinfo[Control]_" undo
+  bindkey "$keyinfo[Escape]_" redo
 
   # Search character.
-  bindkey "${keyinfo[Control]}]" vi-find-next-char
-  bindkey "${keyinfo[Escape]}${keyinfo[Control]}]" vi-find-prev-char
+  bindkey "$keyinfo[Control]]" vi-find-next-char
+  bindkey "$keyinfo[Escape]$keyinfo[Control]]" vi-find-prev-char
 
   # Edit command in an external editor.
-  bindkey "${keyinfo[Control]}x${keyinfo[Control]}e" edit-command-line
+  bindkey "$keyinfo[Control]x$keyinfo[Control]e" edit-command-line
 
   # Expand .... to ../..
   if check-bool "$DOT_EXPANSION"; then
@@ -83,12 +83,12 @@ if [[ "$KEYMAP" == (emacs|) ]]; then
 
   # Bind to history substring search plugin if enabled;
   # otherwise, bind to built-in ZSH history search.
-  if (( ${+widgets[history-incremental-pattern-search-backward]} )); then
-    bindkey "${keyinfo[Control]}r" history-incremental-pattern-search-backward
-    bindkey "${keyinfo[Control]}s" history-incremental-pattern-search-forward
+  if (( $+widgets[history-incremental-pattern-search-backward] )); then
+    bindkey "$keyinfo[Control]r" history-incremental-pattern-search-backward
+    bindkey "$keyinfo[Control]s" history-incremental-pattern-search-forward
   else
-    bindkey "${keyinfo[Control]}r" history-incremental-search-backward
-    bindkey "${keyinfo[Control]}s" history-incremental-search-forward
+    bindkey "$keyinfo[Control]r" history-incremental-search-backward
+    bindkey "$keyinfo[Control]s" history-incremental-search-forward
   fi
 elif [[ "$KEYMAP" == 'vi' ]]; then
   # Use vi key bindings.
@@ -136,7 +136,7 @@ elif [[ "$KEYMAP" == 'vi' ]]; then
 
   # Undo/Redo
   bindkey -M vicmd "u" undo
-  bindkey -M vicmd "${keyinfo[Control]}r" redo
+  bindkey -M vicmd "$keyinfo[Control]r" redo
 
   # Expand .... to ../..
   if check-bool "$DOT_EXPANSION"; then
@@ -148,21 +148,21 @@ elif [[ "$KEYMAP" == 'vi' ]]; then
   bindkey -M viins "kj" vi-cmd-mode
 
   # Emacs key bindings in insert mode.
-  bindkey -M viins "${keyinfo[Control]}a" beginning-of-line
-  bindkey -M viins "${keyinfo[Control]}b" backward-char
-  bindkey -M viins "${keyinfo[Escape]}b" emacs-backward-word
-  bindkey -M viins "${keyinfo[Control]}d" delete-char-or-list
-  bindkey -M viins "${keyinfo[Escape]}d" kill-word
-  bindkey -M viins "${keyinfo[Control]}e" end-of-line
-  bindkey -M viins "${keyinfo[Control]}f" forward-char
-  bindkey -M viins "${keyinfo[Escape]}f" emacs-forward-word
-  bindkey -M viins "${keyinfo[Control]}k" kill-line
-  bindkey -M viins "${keyinfo[Control]}u" backward-kill-line
-  bindkey -M viins "${keyinfo[Control]}w" backward-kill-word
-  bindkey -M viins "${keyinfo[Escape]}w" copy-region-as-kill
-  bindkey -M viins "${keyinfo[Escape]}h" run-help
-  bindkey -M viins "${keyinfo[Escape]}${keyinfo[Left]}" emacs-backward-word
-  bindkey -M viins "${keyinfo[Escape]}${keyinfo[Right]}" emacs-forward-word
+  bindkey -M viins "$keyinfo[Control]a" beginning-of-line
+  bindkey -M viins "$keyinfo[Control]b" backward-char
+  bindkey -M viins "$keyinfo[Escape]b" emacs-backward-word
+  bindkey -M viins "$keyinfo[Control]d" delete-char-or-list
+  bindkey -M viins "$keyinfo[Escape]d" kill-word
+  bindkey -M viins "$keyinfo[Control]e" end-of-line
+  bindkey -M viins "$keyinfo[Control]f" forward-char
+  bindkey -M viins "$keyinfo[Escape]f" emacs-forward-word
+  bindkey -M viins "$keyinfo[Control]k" kill-line
+  bindkey -M viins "$keyinfo[Control]u" backward-kill-line
+  bindkey -M viins "$keyinfo[Control]w" backward-kill-word
+  bindkey -M viins "$keyinfo[Escape]w" copy-region-as-kill
+  bindkey -M viins "$keyinfo[Escape]h" run-help
+  bindkey -M viins "$keyinfo[Escape]$keyinfo[Left]" emacs-backward-word
+  bindkey -M viins "$keyinfo[Escape]$keyinfo[Right]" emacs-forward-word
 
   # History
   bindkey -M vicmd "gg" beginning-of-history
@@ -178,20 +178,20 @@ elif [[ "$KEYMAP" == 'vi' ]]; then
     bindkey -M vicmd "j" down-line-or-history
   fi
 
-  if (( ${+widgets[history-incremental-pattern-search-backward]} )); then
+  if (( $+widgets[history-incremental-pattern-search-backward] )); then
     bindkey -M vicmd "?" history-incremental-pattern-search-backward
     bindkey -M vicmd "/" history-incremental-pattern-search-forward
 
     # Emacs key bindings in insert mode.
-    bindkey -M viins "${keyinfo[Control]}r" history-incremental-pattern-search-backward
-    bindkey -M viins "${keyinfo[Control]}s" history-incremental-pattern-search-forward
+    bindkey -M viins "$keyinfo[Control]r" history-incremental-pattern-search-backward
+    bindkey -M viins "$keyinfo[Control]s" history-incremental-pattern-search-forward
   else
     bindkey -M vicmd "?" history-incremental-search-backward
     bindkey -M vicmd "/" history-incremental-search-forward
 
     # Emacs key bindings in insert mode.
-    bindkey -M viins "${keyinfo[Control]}r" history-incremental-search-backward
-    bindkey -M viins "${keyinfo[Control]}s" history-incremental-search-forward
+    bindkey -M viins "$keyinfo[Control]r" history-incremental-search-backward
+    bindkey -M viins "$keyinfo[Control]s" history-incremental-search-forward
   fi
 else
   echo "oh-my-zsh: KEYMAP must be set 'emacs' or 'vi' but is set to '$KEYMAP'" >&2
@@ -199,45 +199,45 @@ else
 fi
 
 # The next key bindings are for both Emacs and Vi.
-bindkey "${keyinfo[Home]}" beginning-of-line
-bindkey "${keyinfo[End]}" end-of-line
+bindkey "$keyinfo[Home]" beginning-of-line
+bindkey "$keyinfo[End]" end-of-line
 
-bindkey "${keyinfo[Insert]}" overwrite-mode
-bindkey "${keyinfo[Delete]}" delete-char
-bindkey "${keyinfo[Backspace]}" backward-delete-char
+bindkey "$keyinfo[Insert]" overwrite-mode
+bindkey "$keyinfo[Delete]" delete-char
+bindkey "$keyinfo[Backspace]" backward-delete-char
 
-bindkey "${keyinfo[Left]}" backward-char
-bindkey "${keyinfo[Right]}" forward-char
+bindkey "$keyinfo[Left]" backward-char
+bindkey "$keyinfo[Right]" forward-char
 
 # Expand history on space.
 bindkey ' ' magic-space
 
 if (( $+plugins[(er)history-substring-search] )); then
-  bindkey "${keyinfo[Up]}" history-substring-search-up
-  bindkey "${keyinfo[Down]}" history-substring-search-down
-  bindkey "${keyinfo[Control]}p" history-substring-search-up
-  bindkey "${keyinfo[Control]}n" history-substring-search-down
+  bindkey "$keyinfo[Up]" history-substring-search-up
+  bindkey "$keyinfo[Down]" history-substring-search-down
+  bindkey "$keyinfo[Control]p" history-substring-search-up
+  bindkey "$keyinfo[Control]n" history-substring-search-down
 else
-  bindkey "${keyinfo[Up]}" up-line-or-history
-  bindkey "${keyinfo[Down]}" down-line-or-history
-  bindkey "${keyinfo[Control]}p" up-line-or-history
-  bindkey "${keyinfo[Control]}n" down-line-or-history
+  bindkey "$keyinfo[Up]" up-line-or-history
+  bindkey "$keyinfo[Down]" down-line-or-history
+  bindkey "$keyinfo[Control]p" up-line-or-history
+  bindkey "$keyinfo[Control]n" down-line-or-history
 fi
 
 # Clear screen.
-bindkey "${keyinfo[Control]}l" clear-screen
+bindkey "$keyinfo[Control]l" clear-screen
 
 # Expand command name to full path.
-bindkey "${keyinfo[Escape]}e" expand-cmd-path
+bindkey "$keyinfo[Escape]e" expand-cmd-path
 
 # Duplicate the previous word.
-bindkey "${keyinfo[Escape]}m" copy-prev-shell-word
+bindkey "$keyinfo[Escape]m" copy-prev-shell-word
 
 # Bind Shift + Tab to go to the previous menu item.
-bindkey "${keyinfo[BackTab]}" reverse-menu-complete
+bindkey "$keyinfo[BackTab]" reverse-menu-complete
 
 # Complete in the middle of word.
-bindkey "${keyinfo[Control]}i" expand-or-complete-prefix
+bindkey "$keyinfo[Control]i" expand-or-complete-prefix
 
 # Convert .... to ../.. automatically.
 if check-bool "$DOT_EXPANSION"; then
@@ -263,6 +263,6 @@ if check-bool "$COMPLETION_INDICATOR"; then
     zle redisplay
   }
   zle -N expand-or-complete-prefix-with-indicator
-  bindkey "${keyinfo[Control]}i" expand-or-complete-prefix-with-indicator
+  bindkey "$keyinfo[Control]i" expand-or-complete-prefix-with-indicator
 fi