在Perl中获取堆栈跟踪？

Question

如何在Perl中获取堆栈跟踪？

Answer 1

有许多有用的，cor e和基于CPAN的工具来生成堆栈跟踪（如其他答案所示）。但是，如果您想自己推出，请查看caller内置。您可以使用它沿着堆栈走，看看到底发生了什么。

Answer 2

Carp::confess（来自use Carp;）会给你一个完整的堆栈跟踪作为错误的一部分。如果你只是需要它作为失败的一部分，confess是你真正需要的。

每评论，这里有各种Carp功能输出：

use strict; 
use warnings; 
use Carp qw/longmess cluck confess/; 

sub foo { 
    &bar; 
} 

sub bar { 
    &baz; 
} 

sub baz { 
    shift->(); 
} 

my %tests = (
    'longmess' => sub { print longmess 'longmess' }, 
    'cluck' => sub { cluck 'using cluck' }, 
    'confess' => sub { confess 'using confess' }, 
); 

while (my ($name, $sub) = each %tests) { 
    print "$name - before eval:\n"; 
    eval { 
     foo($sub); 
    }; 
    print "$name - before if:\n"; 
    if ($@) { 
     print "caught: $@"; 
    } 
    print "$name - done\n\n"; 
} 

运行此脚本，您可以：

 
longmess - before eval: 
longmess at - line 14 
     main::baz called at - line 10 
     main::bar called at - line 6 
     main::foo('CODE(0x183a4d0)') called at - line 26 
     eval {...} called at - line 25 
longmess - before if: 
longmess - done 

confess - before eval: 
confess - before if: 
caught: using confess at - line 20 
     main::__ANON__() called at - line 14 
     main::baz called at - line 10 
     main::bar called at - line 6 
     main::foo('CODE(0x183a3e0)') called at - line 26 
     eval {...} called at - line 25 
confess - done 

cluck - before eval: 
using cluck at - line 19 
     main::__ANON__() called at - line 14 
     main::baz called at - line 10 
     main::bar called at - line 6 
     main::foo('CODE(0x183a434)') called at - line 26 
     eval {...} called at - line 25 
cluck - before if: 
cluck - done 

运行此脚本，但重定向STDOUT（从而表现出什么被印在STDERR） ，你得到：

 
using cluck at - line 19 
     main::__ANON__() called at - line 14 
     main::baz called at - line 10 
     main::bar called at - line 6 
     main::foo('CODE(0x183a434)') called at - line 26 
     eval {...} called at - line 25 

Answer 3

对于调试需求，我喜欢Carp::Always。

perl -MCarp::Always my_script.pl 

Answer 4

简单的方法使用caller。 此代码不使用任何其他模块。只要在需要的地方包括它。

my $i = 1; 
print "Stack Trace:\n"; 
while ((my @call_details = (caller($i++)))){ 
    print $call_details[1].":".$call_details[2]." in function ".$call_details[3]."\n"; 
}