Concerning hash operations (appending, concatenating)

[RazorbladeBidet]

While working on a program, I was using some hashes in various places. Declaring it in one place with default data and appending to it at a later point.

My question is this: There is a "." operator for concatenation strings (scalars), correct? Is there any equivalent to this for hashes?

i.e.

  my %hash = ( a => 'b' );
  # do stuff
  %hash .= ( e => 'f', g => 'h', i => 'j' );

instead of the semi-tedious

 $hash{'e'} = 'f';
 $hash{'g'} = 'h';
 $hash{'i'} = 'j';

or the seemingly ineffecient (?)

  my @vals = qw( f h j );
  my $i = 0;
  $hash{$_} = $vals[$i++] foreach qw( e g i );

also, how about combining hashes? If not, what method is best for this? Would it be prudent to overload operators to include this kind of functionality (., .=) for hashes?

This is mostly just to satisfy curiosity and, of course, to learn as much as possible :)

Thanks!