DB<113> @array = (a =>1,b=>2)
 => ("a", 1, "b", 2)

  DB<114> while ( my ($key,$val) = splice(@array,0,2) ) {
           $hash{$key}=$val;
          }

  DB<115> \%hash
 => { a => 1, b => 2 }

  DB<116> \@array            # emptied! 
 => []

##</code><code>##

while(@array) {
   $hash{shift @array} = shift @array;
}

##</code><code>##

  DB<108> @array = ( a => 1, b => 2 )
 => ("a", 1, "b", 2)

  DB<109> $hash{shift @array} =shift @array while @array

  DB<110> \%hash
 => { 1 => "a", 2 => "b" }