use strict;
use warnings;

my $test = "{0}{1}{2}{3}{4}{5}{6}{7}{8}{9}=";

# All you need to do is to escape the braces

print "Yay" if $test =~ /\{[^\{\}]+\}\{[^\{\}]+\}\{[^\{\}]+\}\{[^\{\}]
++\}\{([^\{\}]+)\}\{([^\{\}]+)\}\{[^\{\}]+\}\{[^\{\}]+\}\{[^\{\}]+\}\{
+[^\{\}]+\}=/;

# better that is nicer written as (DRY. Dont Repeat Yourself)

print "Yay" if $test =~ /
    (:?
        \{            # literal left brace
        [^ \{ \} ]+   # everything but braces
        \}            # literal right brace
    ){10}             # all of the above then times
    =                 # followed by a literal equal sign   
/x;                   # x ignores whitespace
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