my (%foos, %bars);
while( my $line = <DATA> ) {
  chomp $line;
  if ( $line =~ /^foo ([^:]*):([^:]*)$/ ) {
    push( @{ $foos{ $1 } }, $2 );
  } elsif ( $line =~ /^bar ([^:]*):([^:]*)$/ ) {
    push( @{ $bars{ $1 } }, $2 );
  } else {
#    warn qq( "$line" is the wrong format.\n );
  }
}

##</code><code>##

my (%foos, %bars);
while( my $line = <DATA> ) {
  chomp $line;
  if ( line =~ /^foo (?<KEY>[^:]*):(?<VAL>[^:]*)$/ ) {
    push( @{ $foos{ $+{KEY} } }, $+{VAL} );
  } elsif ( $line =~ /^bar (?<KEY>[^:]*):(?<VAL>[^:]*)$/ ) {
    push( @{ $bars{ $+{KEY} } }, $+{VAL} );
  } else {
#    warn qq( "$line" is the wrong format.\n );
  }
}