While migrating code from 5.16 to 5.24 I noticed this deprecation warning to be inconsistent

according to perldelta all literal left braces should be escaped now.

A literal "{" should now be escaped in a pattern

If you want a literal left curly bracket (also called a left brace) in a regular expression pattern, you should now escape it by either preceding it with a backslash ("\{") or enclosing it within square brackets "[{]" , or by using \Q; otherwise a deprecation warning will be raised. This was first announced as forthcoming in the v5.16 release; it will allow future extensions to the language to happen.

but the following code only warns for the second left brace one. Not escaping the first one doesn't throw a warning.

Am I missing something or is this a bug?

  DB<31>  (my $x="{{abc}}") =~ s/{{/[[/g; print $x

Unescaped left brace in regex is deprecated, passed through in regex; 
+marked by <-- HERE in m/{{ <-- HERE / at (eval 40)[c:/Perl_524/lib/pe
+rl5db.pl:737] line 2.                                                
+                                 at (eval 40)[c:/Perl_524/lib/perl5db
+.pl:737] line 2.                                   eval 'no strict; (
+$@, $!, $^E, $,, $/, $\\, $^W) = @DB::saved;package main; $^D = $^D |
+ $DB::db_stop;                                                   (my 
+$x="{{abc}}") =~ s/{{/[[/g; print $x;                                
+       ' called at c:/Perl_524/lib/perl5db.pl line 737               
+                          DB::eval called at c:/Perl_524/lib/perl5db.
+pl line 3131                         DB::DB called at -e line 1      
+                                        [[abc}}                      
+                                                                     
+                                                                

  DB<32>  (my $x="{{abc}}") =~ s/{\{/[[/g; print $x                   
+          [[abc}}

[download]

PS: sorry for the missing \n in the code, but copying from win-cmd is a PITA

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Je suis Charlie!

In reply to Only sometimes deprecated? "Unescaped left brace in regex is deprecated" by LanX

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