>perl -wMstrict -le
"my $text = 'foo size=\"10\">HHili1 bar size=\"10\">HHili22 baz';
 print qq{'$text'};
 ;;
 $text =~ s/size=\"10\">HHili(\d{1,2})/size=\"10\" text-anchor=\"end\">HHili$1/g;
 print qq{'$text'};
 ;;
 my $toxt = 'fee size=\"10\">HHili1 fie size=\"10\">HHili22 foe';
 print qq{'$toxt'};
 ;;
 my $pre  = qr{ size=\"10\"   }xms;
 my $post = qr{ >HHili\d{1,2} }xms;
 my $insert = ' text-anchor=\"end\"';
 $toxt =~ s{ ($pre) ($post) }{$1$insert$2}xmsg;
 print qq{'$toxt'};
"
'foo size="10">HHili1 bar size="10">HHili22 baz'
'foo size="10" text-anchor="end">HHili1 bar size="10" text-anchor="end">HHili22
baz'
'fee size="10">HHili1 fie size="10">HHili22 foe'
'fee size="10" text-anchor="end">HHili1 fie size="10" text-anchor="end">HHili22
foe'