为什么Perl 6的尝试不处理shell()中的非零退出? [英] Why doesn't Perl 6's try handle a non-zero exit in shell()?

问题描述

此 try 捕获到异常:

try die X::AdHoc;
say "Got to the end";

输出显示程序继续:

 Got to the end

如果我尝试使用 shell 和一个不以0退出的命令，则尝试无法捕获它:

If I attempt it with shell and a command that doesn't exit with 0, the try doesn't catch it:

try shell('/usr/bin/false');
say "Got to the end";

输出看起来不是异常:

The spawned command '/usr/bin/false' exited unsuccessfully (exit code: 1)
  in block <unit> at ... line ...

这到底是怎么回事?

推荐答案

答案确实由乔纳森·沃辛顿(Jonathan Worthington)提供:

The answer is really provided by Jonathan Worthington:

https://irclog.perlgeek.de/perl6-dev/2017-04-04#i_14372945

简而言之，shell()返回一个Proc对象.该对象下沉的那一刻，如果运行程序失败，它将引发内部异常.

In short, shell() returns a Proc object. The moment that object is sunk, it will throw the exception that it has internally if running the program failed.

$ 6 'dd shell("/usr/bin/false")'
Proc.new(in => IO::Pipe, out => IO::Pipe, err => IO::Pipe, exitcode => 1, signal => 0, command => ["/usr/bin/false"])

因此，您需要做的是将Proc对象捕获到变量中，以防止其沉没:

So, what you need to do is catch the Proc object in a variable, to prevent it from being sunk:

$ 6 'my $result = shell("/usr/bin/false"); say "Got to the end"'
Got to the end

然后您可以使用$ result.exitcode来查看它是否成功.

And then you can use $result.exitcode to see whether it was successful or not.

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