#!/bin/bash
# m4.sh: Using the m4 macro processor

# Strings
string=abcdA01
echo "len($string)" | m4                            #   7
echo "substr($string,4)" | m4                       # A01
echo "regexp($string,[0-1][0-1],\&Z)" | m4      # 01Z

# Arithmetic
var=99
echo "incr($var)" | m4                              #  100
echo "eval($var / 3)" | m4                          #   33

exit