*hint* from_to does decode and encode inplace.

saludos,
--shmem

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

from_to does decode and encode inplace

Yes, that's what the documentation says. I'm using it accordingly, so no surprises here.

perl -MEncode -e '$_="\xc1mbito"; print $_; $_ = decode "iso-8859-1", $_; print encode "utf-8", $_'

So you are using decode to translate the input from ISO-8859-1 to "Perl's internal form", whatever it is, and then encode to print it out in the desired encoding. That's two calls, and I thing this "problem" could be solved with just one, after all it's a simple matter of changing the encoding of a string! The gotcha may be in that I'm cheating by assuming that "Perl's internal form" is UTF-8 (I think it is but I shouldn't be assuming it anyway). So what I was trying was to decode the ISO-8859-1 input into UTF-8 with a call to decode and then use it without further modification (this is the third example in the OP; the others are just for illustrating the issue).

Your snippet makes sense and agrees with what I've read recently somewhere, that says that data should be decoded when acquired, then used within the program and finally encoded again when giving it back to the outside world.

--
David Serrano

The -COE sets for utf8 output, and binmode sets the STDIN for latin1.

perl -COE -npe 'BEGIN{binmode q(:encoding(latin1))} ' < file

The -COE sets for utf8 output

Nice to know :^).

However, I'm not getting data from a filehandle, but from an XML::Simple object. It's been my mistake not reflecting it clearly at the first attempt. I've updated the OP in the hope that it's better stated now.

--
David Serrano

I've decided to use Encode to translate data to UTF-8 as soon as I download it. However, Perl is laughing at my attempts (the string is "Ámbito" in ISO-8859-1 and UTF-8 encodings)

Single-byte values in the range \x80-\xFF have a somewhat ambiguous, magical status in perl 5.8; they may be either single-byte values or "wide" utf8 characters, depending on the how they are used. Consider:

perl -e 'print "\xc1\n"' | xxd -g1
0000000: c1 0a                                          ..

perl -CO -e 'print "\xc1\n"' | xxd -g1
0000000: c3 81 0a                                       ...
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While playing with examples, I also came across the following, which might be instructive (if not too confusing):

$ perl -MEncode -e '$x="\xc1";
$y = decode("iso-8859-1",$x);   # $y has utf8 flag set
$c = ( $x eq $y ) ? "eq":"ne"; 
print "$x $c $y\n";' | od -ctxC

0000000  301       e   q     301  \n                                  
+  
           c1  20  65  71  20  c1  0a                                 
+   
0000007

$ perl -MEncode -e '$x="\xc1";
$y = encode("utf8",$x);         # utf8 flag is not set
$c = ( $x eq $y ) ? "eq":"ne"; 
print "$x $c $y\n";' | od -ctxC
0000000  301       n   e     303 201  \n                              
+  
           c1  20  6e  65  20  c3  81  0a                             
+   
0000010
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The first case indicates why characters in the range 80-FF have special status in perl 5.8 (and why it's easy to get confused): they seem to be stored internally as single bytes, even when the scalar containing them is explicitly flagged as a utf8 string; whether they are single-byte or "wide" on output depends on whether you've done "binmode ':utf8'" on the given file handle. I gather this is a kind of "interim solution" intended to make a larger class of common situations "easier" to deal with (even though this default behavior is logically inconsistent with the Unicode Standard).

The second case shows how to assign the actual two-byte utf8 sequence for Á to a scalar, but this makes it "alien" to the perl-5.8 way of doing things. (Adding "-CO" to both cases yields predictable results.)

Anyway, if your problem is displaying PerlMonks pages or other 8859-1 text as utf8 data (which means converting from single-byte-per-char to variable-width-char), the following will suffice:

perl -pe 'BEGIN{binmode STDOUT,":utf8"}' < file.iso > file.utf8

# or, using the more cryptic "-C" option:

perl -CO -pe '' < file.iso > file.utf8
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