perl"或"错误处理:错误的多语句可能吗？

Question

这个结构在perl中很常见:

opendir (B,"/somedir") or die "couldn't open dir!";

但这似乎不起作用:

opendir ( B, "/does-not-exist " ) or {
    print "sorry, that directory doesn't exist.\n";
    print "now I eat fugu.\n";
    exit 1;
};

"或"错误处理是否有可能有多个命令？

编译以上内容:

# perl -c test.pl
syntax error at test.pl line 5, near "print"
syntax error at test.pl line 7, near "}"
test.pl had compilation errors.

Answer 1

你可以随时使用do:

opendir ( B, "/does-not-exist " ) or do {
    print "sorry, that directory doesn't exist.\n";
    print "now I eat fugu.\n";
    exit 1;
}

或者您可以使用if/unless:

unless (opendir ( B, "/does-not-exist " )) {
    print "sorry, that directory doesn't exist.\n";
    print "now I eat fugu.\n";
    exit 1;
}

或者你可以把你自己的子程序放在一起:

opendir ( B, "/does-not-exist " ) or fugu();

sub fugu {
    print "sorry, that directory doesn't exist.\n";
    print "now I eat fugu.\n";
    exit 1;
}

有不止一种方法可以做到这一点.