I have had a Perl Website working for 7 years and have had no problems
until at the weekend I replace my perl version with a newer one.

Perl version (old): Perl5.10
Perl version (new): Perl5.26.3

I run following code in Perl5.10, it return my expected result.

 if ($str =~ /(\\x{[A-F\d]+})/i){

However after i migrated to Perl5.26.3, i hit following error:

********** Error **********
Unescaped left brace in regex is passed through in regex; marked by <-- HERE in m/(\\x{ <-- HERE A-F\d+})/ at test.pl line 6.
********** Error **********

Of course, the most reliable way to deal with it is to
escape the brace by preceding them with a backslash ("\{" ),
but the application is large and escape is a terrible job.

Is there any easy way to maintain compatibility?

In reply to Unescaped left brace in regex is passed through in regex by gzh

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