m4.sh

来自「一本完整的描述Unix Shell 编程的工具书的所有范例」· Shell 代码 · 共 15 行

#!/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
echo "incr(22)" | m4                               # 23
echo "eval(99 / 3)" | m4                           # 33

exit 0