It's strange that the message is printed twice since it is being called once!!! Why?

I added some code lines to trace the handlers at any moment, but as $ua->handlers() require an HTTP::Response object, I had to split the $ua->get() calls, and an extra call must be added at the beginning, giving:

#!perl

use strict;
use warnings;

use LWP::UserAgent qw( );

my $ua = LWP::UserAgent->new();
my $url = 'http://www.google.com/';
my $resp;

$resp = $ua->get($url); print($resp->status_line(), "\n");
show(1);
print("Added:\n");
$ua->add_handler(response_header => sub { print "HANDLER\n"; });
show(2);
$resp = $ua->get($url); print($resp->status_line(), "\n");
show(3);
print("Removed:\n");
$ua->remove_handler('response_header');
show(4);
$resp = $ua->get($url); print($resp->status_line(), "\n");
show(5);

sub show {
  print(join(" ", @_, $ua->handlers('response_header', $resp)), "\n");
}

[download]

Output:

200 OK
1 HASH(0x183657c)
Added:
2 HASH(0x183657c) HASH(0x1b79944)
HANDLER
HANDLER
200 OK
3 HASH(0x183657c) HASH(0x1b79944)
Removed:
4
200 OK
5

[download]

It seems that there is a default handler installed, and I would expect that trace lines 4 and 5 to show the same hash as line 1, not an empty list of handlers.

BTW, I changed your original test program to use a WWW::Mechanize object, and got the same output as you.

In reply to Re^2: LWP handlers examples? by vitoco
in thread LWP handlers examples? by vitoco

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