set bail on;
 set list on;
 set names utf8;
 shell del c:\temp\tmp4test.fdb 2>nul;
 create database 'localhost:c:\temp\tmp4test.fdb' default character set utf8;
 show version;
 
 recreate table test(
    id int generated by default as identity constraint pk_txt primary key
   ,txt varchar(1) character set utf8
 );
 
 insert into test(txt) values('A');
 insert into test(txt) values('B'); ---------------------------------- [ 0 ]
 
 set term ^;
 execute block returns(
      o_id type of column test.id
         ,o_txt type of column test.txt
 ) as
         declare b boolean;
 begin
         for select id, txt from test as cursor c
         do begin
             o_id = c.id;
                 o_txt = c.txt;
             suspend;
                 begin
                         b = c.txt similar to 'Ⱥ{0,1}'; ------------ [ 1 ]
                         --b = c.txt similar to 'A{0,1}'; ---------------- [ 2 ]
                 when any do
                         begin
                                 --exception; -------------------------------- [ 3 ]
                         end
                 end
         end
 end
 ^
 set term ;^
 quit;

 O_ID 1
 O_TXT A
 
 Statement failed, SQLSTATE = 42000
 Invalid SIMILAR TO pattern
 -At block line: 13, col: 4
 -At block line: 17, col: 5