Lo, Given that: 
$self->client->param( 'usr_id' ) returns 1
$self->client->param( 'edit_usr_id' ) returns undef, or something
$self->client->param( 'mode' ) returns 'add'

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How come the below really screws up the hash: 
$self->log(LOGDEBUG, 'EDIT_USER: '. Dumper(
    { state       => 'db_user',
    usr_id      => $self->client->param( 'usr_id' ),
    edit_usr_id => $self->client->param( 'edit_usr_id' ),
    mode        => $self->client->param( 'mode' )
    }));

 EDIT_USER: $VAR1 = {
          'add' => undef,
          'usr_id' => '1',
          'edit_usr_id' => 'mode',
          'state' => 'db_user'
        };

[download]
And yet doing it this way is as expected: 

my $a = $self->client->param( 'edit_usr_id' );

$self->log(LOGDEBUG, 'EDIT_USER: '. Dumper(
    { state       => 'db_user',
    usr_id      => $self->client->param( 'usr_id' ),
    edit_usr_id => $a,
    mode        => $self->client->param( 'mode' )
    }));


 EDIT_USER: $VAR1 = {
          'usr_id' => '1',
          'mode' => 'add',
          'edit_usr_id' => undef,
          'state' => 'db_user'
        };

[download]

In reply to mysterious hash ref result by ftumsh

Title:
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