handling unmet dependencies

- will prompt if `realpath` does not exist
- need to work on the heredoc. insert new line for each dep

bak-old.sh

@@ -80,6 +80,16 @@ print_err(){
     exit 1
 }
 
+print_err_deps(){
+    tput setaf 1
+    cat <<- EOF
+	${0##*/} has the following unmet dependencies:
+	${1/:/\\n}
+	EOF
+    tput sgr0
+    exit 1
+}
+
 copy_succ(){
     echo " ✅ $(tput setaf 2; tput bold)${1}.${2:-bak}$(tput sgr0)"
 }
@@ -168,6 +178,23 @@ parse_combined(){
 ${DEBUG+debug}       ###
 ### if $DEBUG is set ###
 
+###############################################################################
+# CHECKING DEPS
+##################
+deps=(realpath)
+
+for dep in $deps; do
+    if command -v "$dep"; then
+	continue
+    else
+	missing="${dep}:"
+    fi
+done
+
+if [[ -n ${missing} ]]; then
+    print_err_deps $missing
+fi
+
 ###############################################################################
 # SANITISING PARAMS AND OPTIONS
 ##################################