diff --git a/functions/icons.zsh b/functions/icons.zsh
index ca7b2b0a..d1cccffd 100755
--- a/functions/icons.zsh
+++ b/functions/icons.zsh
@@ -550,8 +550,8 @@ function _p9k_init_icons() {
 function print_icon() {
   local icon_name=$1
   local var_name=POWERLEVEL9K_${icon_name}
-  if [[ -v "$var_name" ]]; then
-    echo -n "${(P)ICON_USER_VARIABLE}"
+  if [[ -n "${(tP)var_name}" ]]; then
+    echo -n "${(P)var_name}"
   else
     echo -n "${icons[$icon_name]}"
   fi
diff --git a/functions/utilities.zsh b/functions/utilities.zsh
index 7a322e57..9821b287 100755
--- a/functions/utilities.zsh
+++ b/functions/utilities.zsh
@@ -22,7 +22,7 @@ function set_default() {
 
   local varname=$1
   shift
-  if [[ -v $varname ]]; then
+  if [[ -n ${(tP)varname} ]]; then
     typeset $flags $varname
   elif [[ "$flags" == *[aA]* ]]; then
     eval "typeset ${(@q)flags} ${(q)varname}=(${(qq)@})"
diff --git a/powerlevel9k.zsh-theme b/powerlevel9k.zsh-theme
index 040e717f..242c8cc9 100755
--- a/powerlevel9k.zsh-theme
+++ b/powerlevel9k.zsh-theme
@@ -55,7 +55,7 @@ if ! autoload -U is-at-least || ! is-at-least 5.2; then
   return 1
 fi
 
-if [[ -v _P9K_SOURCED ]]; then
+if (( $+_P9K_SOURCED )); then
   prompt_powerlevel9k_setup "$@"
   return
 fi
@@ -1608,7 +1608,7 @@ powerlevel9k_vcs_init() {
   local component state
   for component in REMOTE_URL COMMIT BRANCH TAG REMOTE_BRANCH STAGED UNSTAGED UNTRACKED \
                    OUTGOING_CHANGES INCOMING_CHANGES STASH ACTION; do
-    local color=${(P):-POWERLEVEL9K_VCS_${component}FORMAT_FOREGROUND}
+    local color=${(P)${:-POWERLEVEL9K_VCS_${component}FORMAT_FOREGROUND}}
     if [[ -n $color ]]; then
       for state in "${(@k)vcs_states}"; do
         local var=POWERLEVEL9K_VCS_${(U)state}_${component}FORMAT_FOREGROUND
@@ -1661,7 +1661,7 @@ typeset -gAH _P9K_LAST_GIT_PROMPT
 typeset -gAH _P9K_GIT_SLOW
 
 function _p9k_vcs_style() {
-  local color=${(P):-POWERLEVEL9K_VCS_${1}_${2}FORMAT_FOREGROUND}
+  local color=${(P)${:-POWERLEVEL9K_VCS_${1}_${2}FORMAT_FOREGROUND}}
   if [[ -z $color ]]; then
     _P9K_RETVAL=""
     return
@@ -1679,7 +1679,7 @@ function _p9k_vcs_style() {
 }
 
 function _p9k_vcs_render() {
-  if [[ -v _P9K_NEXT_VCS_DIR ]]; then
+  if (( $+_P9K_NEXT_VCS_DIR )); then
     local -a msg
     local dir=${${GIT_DIR:a}:-$PWD}
     while true; do
@@ -1864,7 +1864,7 @@ function _p9k_vcs_resume() {
 function _p9k_vcs_gitstatus() {
   [[ $POWERLEVEL9K_DISABLE_GITSTATUS == true ]] && return 1
   if [[ $_P9K_REFRESH_REASON == precmd ]]; then
-    if [[ -v _P9K_NEXT_VCS_DIR ]]; then
+    if (( $+_P9K_NEXT_VCS_DIR )); then
       typeset -gH _P9K_NEXT_VCS_DIR=${${GIT_DIR:a}:-$PWD}
     else
       local dir=${${GIT_DIR:a}:-$PWD}