improve next-in-path handling, fix line endings

lib/next-in-path.zsh

@@ -2,12 +2,19 @@
 # Usage: next-in-path <program name> <current $0>
 typeset -U path
 next-in-path() {
-	entries=( $(which -a $1) )
-	index=${entries[(ie)$2]} 
+	local entries=( $(which -a $1) )
+	local index=${entries[(ie)$2]}
+	local result
 	if [[ $index -le ${#entries} ]]; then
 		# found $0, use next entry
-		echo $entries[$((index + 1))]
+		result=$entries[$((index + 1))]
 	else
-		echo $entries[1]
+		result=$entries[1]
+	fi
+
+	if [[ -n $result ]]; then
+		echo $result
+	else
+		return 1
 	fi
 }