I could not write an example that reproduced this exact behavior, but in the construction: 

   { state       => 'db_user',
    usr_id      => $self->client->param( 'usr_id' ),
    edit_usr_id => $self->client->param( 'edit_usr_id' ),
    mode        => $self->client->param( 'mode' )
    }

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the methods are called in list context, and they may mess with the result if they do not return a list with an odd number of elements. For example, 
$ perl -MData::Dump=dump -e '
        sub f { (1, 2) }; 
        print dump({ a => f, b => 1 })
'

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prints 
{ 1 => undef, 2 => "b", a => 1 }

[download]

As I told, I could not get the same behavior returning an empty list, but I am still investigating. Maybe if you omitted parts in your explanation, this case fits.

In reply to Re: mysterious hash ref result by ferreira
in thread mysterious hash ref result by ftumsh

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