如何绕过无法修改的 Perl 库中的“死"调用? [英] How can I get around a 'die' call in a Perl library I can't modify?

问题描述

是的，问题出在我正在使用的库上，不，我无法修改它.我需要一个解决方法.

Yes, the problem is with a library I'm using, and no, I cannot modify it. I need a workaround.

基本上，我正在处理一个写得很糟糕的 Perl 库，它在读取文件时遇到某个错误条件时以die"退出.我从一个循环数千个文件的程序中调用这个例程，其中一些是坏的.坏文件发生；我只希望我的例程记录错误并继续.

Basically, I'm dealing with a badly written Perl library, that exits with 'die' when a certain error condition is encountered reading a file. I call this routine from a program which is looping through thousands of files, a handful of which are bad. Bad files happen; I just want my routine to log an error and move on.

如果我可以修改库，我会简单地更改

IF I COULD modify the library, I would simply change the

die "error";

到一个

print "error";return;

，但我不能.有什么办法可以让我的例程不那么糟糕，让坏文件不会让整个过程崩溃?

, but I cannot. Is there any way I can couch the routine so that the bad files won't crash the entire process?

后续问题:使用eval"来处理容易崩溃的调用效果很好，但是如何在该框架内设置可捕获错误的处理?描述:

FOLLOWUP QUESTION: Using an "eval" to couch the crash-prone call works nicely, but how do I set up handling for catch-able errors within that framework? To describe:

我有一个子程序，它有时会多次调用库崩溃.与其在这个子例程中的每个调用都使用 eval{}，我只是让它死亡，并在调用我的子例程的级别上使用 eval{}:

I have a subroutine that calls the library-which-crashes-sometimes many times. Rather than couch each call within this subroutine with an eval{}, I just allow it to die, and use an eval{} on the level that calls my subroutine:

my $status=eval{function($param);};
unless($status){print $@; next;}; # print error and go to next file if function() fails

但是，我可以在 function() 中捕捉到一些错误情况.在子例程和调用例程中设计错误捕获的最合适/优雅的方法是什么，以便我为捕获的和未捕获的错误获得正确的行为?

However, there are error conditions that I can and do catch in function(). What is the most proper/elegant way to design the error-catching in the subroutine and the calling routine so that I get the correct behavior for both caught and uncaught errors?

推荐答案

您可以将其包装在 eval 中.见:

You could wrap it in an eval. See:

perldoc -f eval

例如，你可以写:

# warn if routine calls die
eval { routine_might_die }; warn $@ if $@;

这会将致命错误变成警告，这或多或少是您建议的.如果 die 被调用，$@ 包含传递给它的字符串.

This will turn the fatal error into a warning, which is more or less what you suggested. If die is called, $@ contains the string passed to it.

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