How to convert \u0421 into letter "C"? - json

Question

I made a post query to server and got json. It contains wrong symbol: instead "Correct" I got "\u0421orrect". How can I encode this text?
A parse_json function performs it like "РЎorrect";
I found out that
$a = "\x{0421}orrect";
$a= encode("utf-8", $a);
returns "РЎorrect", and
$a = "\x{0421}orrect";
$a= encode("cp1251", $a);
returns "Correct"
So I've decided to change \u to \x and then to use cp1251.
\u to \x
I wrote:
Encode::Escape::enmode 'unicode-escape', 'perl';
Encode::Escape::demode 'unicode-escape', 'python';
$content= encode 'unicode-escape', decode 'unicode-escape', $content;
and got \x{0421}orrect.
And then I tried:
$content = encode( 'cp1251', $content );
And... nothing changed! I still have \x{0421}orrect...
I notice something interesting:
$a = "\x{0421}orrect";
$a= encode("cp1251", $a);
returns "Correct"
BUT
$a = '\x{0421}orrect';
$a= encode("cp1251", $a);
still returns "\x{0421}orrect".
Maybe this is a key, but I don't know what I can do with this.
I've already tried to encode and decode, Encode:: from_to,JSON::XS and utf8.

Answer 1

You mention escaping multiple times, but you want to do the opposite (unescape).
decode_json/from_json will correctly return "Сorrect" (Where the "C" is CYRILLIC CAPITAL LETTER ES).
use JSON::XS qw( decode_json );
my $json_utf8 = '{"value":"\u0421orrect"}';
my $data = decode_json($json_utf8);
You do need to encode your outputs, though. For example, if you have Cyrillic-based Windows system, and you wanted to create a native file, you could use
open(my $fh, '>:encoding(cp1251)', $qfn)
or die("Can't create \"$qfn\": $!\n");
say $fh $data->{value};
If you want to hardcode the encoding, or if you're interested in the encoding output to STDOUT and STDERR as well, check out this.

Answer 2

Apologies if you realise this already - I just think it's worth pointing out so we're all on the same page.
Character number \x{0421} has the description "CYRILLIC CAPITAL LETTER ES" and looks like this: С
Character number \x{0043} has the description "LATIN CAPITAL LETTER C" and looks like this: C
So depending on the font you're using, it's entirely likely that the two characters appear identical.
You asked "How can I encode this text?" but you didn't explain what you mean by that or why you want to "encode" it. There is no encoding that will convert 'С' (\x{0421}) into 'C' (\x{0043}) - they are two different characters from two different alphabets.
So the question is, what are you trying to achieve? Are you trying to check if the string returned from the server matched "Correct"? If so, that simply won't work, because the server is returning the string "Сorrect". They might look the same, but they are two different strings.
It's possible that whole situation is an error in the server code and it should be returning "Correct". If that is the case and you can't rely on the server reliably returning the "Correct", one workaround would be to use a character replacement, to "normalise" the string before you inspect its contents. For example:
use JSON::XS qw( decode_json );
my $response = <<EOF;
{
"status": "\u0421orrect"
}
EOF
my $data = decode_json($response);
my $status = $data->{status};
$status =~ tr/\x{0421}/C/;
if($status eq "Correct") {
say "The status is correct";
}
else {
say "The status is not correct";
}
This code will work now, and in the future if the server code is fixed to return "Correct".