单行注释
# echo "hello world"
多行注释
#!/bin/bash
# author: lne
# url: lne.cc
echo "hello world"
# v1
: '
echo "hello world"
echo 'hello world'
echo `ls -l; mkdir 1`
'
# v2
:<<"eof"
echo "hello world"
echo 'hello world'
echo `ls -l; mkdir 1`
eof
# v3
:<<'!'
echo "hello world!"
echo 'hello world'
echo `ls -l; mkdir 1`
!false
!
# v4
:<<\EOF
echo "hello world!"
echo 'hello world'
echo `ls -l; mkdir 1`
EOF
# v5 注释中不能有单独"}", 包含可导致语法错误
((0)) && {
echo "hello world!"
echo 'hello world'
echo `ls -l; mkdir 1`
}
# v5 注释中不能有单独"}", 包含可导致语法错误
false && {
echo "hello world!"
echo 'hello world'
echo `ls -l; mkdir 1`
}
# v6 注释中不能有单独"fi", 包含可导致语法错误
if false; then
echo "hello world!"
echo 'hello world'
echo `ls -l; mkdir 1`
fi
# v7 注释中不能有单独"done", 包含可意外结束循环
while false; do
echo "hello world!"
echo 'hello world'
echo `ls -l; mkdir 1`
done
# v8 注释中不能有单独"done", 包含可意外结束循环
while :; do
break
echo "hello world!"
echo 'hello world'
echo `ls -l; mkdir 1`
done
# v9 注释中不能有单独"done", 包含可意外结束循环
for false; do
echo "hello world!"
echo 'hello world'
echo `ls -l; mkdir 1`
done
# v10 注释中不能有单独"done", 包含可意外结束循环
for ((;;)); do
break
echo "hello world!"
echo 'hello world'
echo `ls -l; mkdir 1`
done
# v11 注释中不能有单独"done", 包含可意外结束循环
until true; do
echo "hello world!"
echo 'hello world'
echo `ls -l; mkdir 1`
done
# v12 注释中不能有单独"done", 包含可意外结束循环
until :; do
echo "hello world!"
echo 'hello world'
echo `ls -l; mkdir 1`
done
# v13 注释中不能有单独"EOF", 包含可意外结束循环
<<"EOF"
echo "hello world!"
echo 'hello world'
echo `ls -l; mkdir 1`
EOF
# v14 将注释放到函数中
function comment() {
echo "hello world!"
echo 'hello world'
echo `ls -l; mkdir 1`
}