Name : perl-Devel-FindRef
| |
Version : 1.460.0
| Vendor : obs://build_opensuse_org/devel:languages:perl
|
Release : 1.10
| Date : 2018-08-06 07:25:50
|
Group : Unspecified
| Source RPM : perl-Devel-FindRef-1.460.0-1.10.src.rpm
|
Size : 0.05 MB
| |
Packager : (none)
| |
Summary : Where is that reference to my variable hiding?
|
Description :
Tracking down reference problems (e.g. you expect some object to be destroyed, but there are still references to it that keep it alive) can be very hard. Fortunately, perl keeps track of all its values, so tracking references \"backwards\" is usually possible.
The \'track\' function can help track down some of those references back to the variables containing them.
For example, for this fragment:
package Test;
use Devel::FindRef; use Scalar::Util;
our $var = \"hi\ \"; my $global_my = \\$var; our %global_hash = (ukukey => \\$var); our $global_hashref = { ukukey2 => \\$var };
sub testsub { my $testsub_local = $global_hashref; print Devel::FindRef::track \\$var; }
my $closure = sub { my $closure_var = \\$_[0]; Scalar::Util::weaken (my $weak_ref = \\$var); testsub; };
$closure->($var);
The output is as follows (or similar to this, in case I forget to update the manpage after some changes):
SCALAR(0x7cc888) [refcount 6] is +- referenced by REF(0x8abcc8) [refcount 1], which is | the lexical \'$closure_var\' in CODE(0x8abc50) [refcount 4], which is | +- the closure created at tst:18. | +- referenced by REF(0x7d3c58) [refcount 1], which is | | the lexical \'$closure\' in CODE(0x7ae530) [refcount 2], which is | | +- the containing scope for CODE(0x8ab430) [refcount 3], which is | | | the global &Test::testsub. | | +- the main body of the program. | +- the lexical \'&\' in CODE(0x7ae530) [refcount 2], which was seen before. +- referenced by REF(0x7cc7c8) [refcount 1], which is | the lexical \'$global_my\' in CODE(0x7ae530) [refcount 2], which was seen before. +- the global $Test::var. +- referenced by REF(0x7cc558) [refcount 1], which is | the member \'ukukey2\' of HASH(0x7ae140) [refcount 2], which is | +- referenced by REF(0x8abad0) [refcount 1], which is | | the lexical \'$testsub_local\' in CODE(0x8ab430) [refcount 3], which was seen before. | +- referenced by REF(0x8ab4f0) [refcount 1], which is | the global $Test::global_hashref. +- referenced by REF(0x7ae518) [refcount 1], which is | the member \'ukukey\' of HASH(0x7d3bb0) [refcount 1], which is | the global %Test::global_hash. +- referenced by REF(0x7ae2f0) [refcount 1], which is a temporary on the stack.
It is a bit convoluted to read, but basically it says that the value stored in \'$var\' is referenced by:
* - the lexical \'$closure_var\' (0x8abcc8), which is inside an instantiated closure, which in turn is used quite a bit.
* - the package-level lexical \'$global_my\'.
* - the global package variable named \'$Test::var\'.
* - the hash element \'ukukey2\', in the hash in the my variable \'$testsub_local\' in the sub \'Test::testsub\' and also in the hash \'$referenced by Test::hash2\'.
* - the hash element with key \'ukukey\' in the hash stored in \'%Test::hash\'.
* - some anonymous mortalised reference on the stack (which is caused by calling \'track\' with the expression \'\\$var\', which creates the reference).
And all these account for six reference counts.
|
RPM found in directory: /packages/linux-pbone/ftp5.gwdg.de/pub/opensuse/repositories/devel:/languages:/perl/openSUSE_Tumbleweed/i586 |
Hmm ... It's impossible ;-) This RPM doesn't exist on any FTP server
Provides :
perl(Devel::FindRef)
perl-Devel-FindRef
perl-Devel-FindRef(x86-32)
Requires :