Can you used a regex to identify the the characters which are double length ? Something like:

  print xlen("(\x{5fcd}\x{65e0}\x{53ef}\x{5fcd})"), "\n" ; ;

  sub xlen {
    my ($s) = @_ ;
    my $l = length($s) ;
    while ($s =~ m/[\x{5000}-\x{6FFF}]/g) { $l++ ; } ;
    return $l ;
  } ;

[download]
perhaps ?

Or:

  print ylen("(\x{5fcd}\x{65e0}\x{53ef}\x{5fcd})"), "\n" ; ;

  sub ylen {
    my ($s) = @_ ;
    return length($s) + ($s =~ tr/[\x{5000}-\x{6FFF}]//) ;
  } ;

[download]
which avoids running a while loop and may or may not be faster.

In reply to Re: The “real length" of UTF8 strings by gone2015
in thread The “real length" of UTF8 strings by Anonymous Monk

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