#!/bin/bash

function log () {
   # if argument is given, echo argument, if stream is piped, echo each line of stream
   if [ "$verbosity" != 'VERBOSE' ] ; then return 0; fi
   if [ -n "$1" ]; then
      echo "$1"
   else
      while read line
      do
         if [ -n "$line" ]; then
            echo "$line"
         fi
      done
   fi
}

function error () {
   # if argument is given, echo argument to stderr, if stream is piped, echo each line of stream to stderr
   if [ "$verbosity" = 'SILENT' ]; then return 0; fi
   if [ -n "$1" ]; then
      echo "$1" >&2
   else
      while read line
      do
         if [ -n "$line" ]; then
            echo "$line" >&2
         fi
      done
   fi
}