Good time! Not that it is my first script in PERL, yet I can not understand why I have such a problem w/ following simple cycle: 
do{
  $index_cur=int( rand( ( $last_abc_letter ) ) );
  if( $index_cur==$index_prev ){
    next;
  }else{
    $index_prev=$index_cur;
    print "$letter[$index_cur]\n";
    $key=&ReadKey( 0 );
  }
}until $key eq 'q';

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But at run time after several successful cycles I get (when $index_cur==$index_prev): Can't "next" outside a loop block... So, it seems that next supposes it stands out of do-until. Why is so? How I can fix the issue?

In reply to do-until: Can't "next" outside a loop block. by humble

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