perlnotes: 正则中的/e和/ee

/e = eval 'code' 不会对code进行插值
//e = eval "code" 会对code进行插值

my $str = 'My name is $name' ##$name="foo" and you want to substitute $name by foo
$str =~ s/(\$\w)+/\1/gee \1获得$name, /ee对$name插值获得foo