Add more utility functions

rowbot

@@ -120,6 +120,35 @@ die() {
   exit "${STATUS:-42}"
 }
 
+get_option() {
+  if (( $# != 2 )); then
+    return 1
+  fi
+
+  local option_name=${1//-/_}
+  declare -n option_var=$option_name
+
+  if [[ -v opts[$1] ]]; then
+    option_var=${opts[log-level]}
+  elif [[ ! -v $option_name ]]; then
+    # This variable is only used for assignment.
+    # shellcheck disable=SC2034
+    option_var=$2
+  fi
+}
+
+has() {
+  if (( $# )); then
+    hash "$1" 2>/dev/null
+  else
+    return 1
+  fi
+}
+
+is_parent() {
+  (( BASHPID == $$ ))
+}
+
 is_reloaded() {
   [[ $RELOADED = yes ]] || (( LORE_LIVES > 1 ))
 }