1) Because
transaction $bdh => code{ ... }
reads better than
transaction $bdh, sub { ... }
. That's the only reason.
2) Well, it may contain the filename&linenumber of the original error message, but not of the place where the transaction ends and where therefore it's commited or rolled back. I think it makes more sense to append the position of the closing brace of the transaction block than some line within Transaction.pm. Try to throw an exception within a second level transaction. You'll end up with something like:
Some error
commit not safe after errors, transaction rolled back at Transactions.
+pm line 123
commit not safe after errors, transaction rolled back at Transactions.
+pm line 123
Not very helpfull I'd think :-)
Here is the script I used to test my version of the module:
use Transactions;
package Foo;
sub begin_work {
my $self = shift();
print "CALL begin_work on $self->{name}\n";
}
sub rollback {
my $self = shift();
print "CALL rollback on $self->{name}\n";
}
sub commit {
my $self = shift();
print "CALL commit on $self->{name}\n";
}
sub new {
bless {name => $_[1]}, $_[0];
}
package main;
$foo = new Foo 'jenda';
$foo1 = new Foo 'pavel';
$foo2 = new Foo 'martin';
#eval {
transaction $foo => code{
print "Start of the outer transaction\n";
# die "Some error\n";
# eval {
transaction [$foo1, $foo2] => code{
print "Start of the inner transaction\n";
die "Some error\n";
print "End of the inner transaction\n";
};
# };
# if ($@) {print "Error in inner trans: $@\nIGNORING!!!\n"};
# die "Some error\n";
print "End of the outer transaction\n";
};
#};
transaction $foo => code{
print "Start of the outer transaction\n";
print "End of the outer transaction\n";
};
Jenda
Always code as if the guy who ends up maintaining your code
will be a violent psychopath who knows where you live.
-- Rick Osborne
Edit by castaway: Closed small tag in signature
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