closes #1

yt

@@ -18,6 +18,15 @@
 
 set -e
 
+test -z "$DEBUG" || set -x
+
+argv0="$0"
+com="$1"
+
+cachefile="$XDG_CACHE_HOME/yt.cache"
+FMT='%(title)s – %(channel)s (%(duration>%H:%M:%S)s) [%(webpage_url)s]'
+WBAPI='https://archive.org/wayback/available?url='
+
 add() { # adds a video to a playlist file
 	while test -n "$2"; do
 		if test -n "$(grep -e "$1" "$2")"
@@ -56,6 +65,12 @@ archive() { # archives a video to the Wayback Machine
 }
 
 cache() { # cache the video title for faster retrieval
+	if test -z "$XDG_CACHE_HOME"; then
+		printf "%s: unable to create title cachefile: \$XDG_CACHE_HOME unset." \
+			"$argv0" 2>&1
+		exit 69 # sysexits.h(3) EX_UNAVAILABLE
+	fi
+
 	while test -n "$1"; do
 		grep "$1" "$cachefile" 2>/dev/null 1>&2 || printf '%s\n' \
 			"$(yt-dlp -s "$1" --print "$FMT")" >>"$cachefile"
@@ -85,6 +100,11 @@ music() { # downloads a video, splitting by chapter and only saving the audio
 }
 
 pick() { # Pick a video to play from a list of videos
+	if test -z "$YTPICK"; then
+		printf "%s: Please set \$YTPICK to your preferred picking tool." "$argv0" 1>&2
+		exit 78 # sysexits.h(3) EX_CONFIG
+	fi
+
 	while test -n "$1"; do
 		for line in $(lines "$1"); do
 			if test -n "$(printf '%s\n' "$line" | sed -n '/^\#/p')"
@@ -165,22 +185,6 @@ verify() { # replaces videos with archived versions if they are not available
 	done
 }
 
-argv0="$0"
-com="$1"
-
-cachefile="$XDG_CACHE_HOME/yt.cache"
-FMT='%(title)s – %(channel)s (%(duration>%H:%M:%S)s) [%(webpage_url)s]'
-WBAPI='https://archive.org/wayback/available?url='
-
-if test -z "$YTPICK"; then
-	printf "%s: Please set \$YTPICK to your preferred picking tool." "$argv0" 1>&2
-	exit 78 # sysexits.h(3) EX_CONFIG
-fi
-
-if test -n "$DEBUG"; then
-	set -x
-fi
-
 for dep in \
 	curl \
 	jq \