Question

I am so confused by the unicode and unicode in perl.

I got this hash from MySQL db.

my $hashFromDB = { "Ves\x{101}kha" => "some value" };

But I only know the key in this form of notation

my $key = "Ves\u0101kha";

How can I convert that \uXXXX notation to that \x{xxx} so that I can get the value with the key.

Thanks.

Answer 1

\x{} escape in Perl works almost exactly like \u escape in JS. You simply use code inside {}, exactly as in your first snippet:

my $key = "Ves\x{101}kha";
my $value = $hashFromDB->{$key};

If you have literal string with \u in it, which I assume means “\u followed with 4 hexadecimal digits to form codepoint number”, just preprocess it with regexp that would replace such sequences with real characters with same code:

$key =~ s/\\u([a-fA-F0-9]{4})/chr(hex($1))/ge;

BTW, \u have different meaning in Perl – it upercases next symbol. You can check complete list of escapes in documentation.