use Regexp::Common;
use strict;
my @examples = (
    '${ThisOne}',
    'do not match me %{}',
    '${This${One}}',
    '${This${One}Too}',
    '${This${One}and${also}this}',
    'me either $}',
    'dont match this line noise {} $ }{'
);

foreach (@examples){
    print "$_\n" if  /(\$$RE{balanced}{-parens=>'{}'})/;
}
my $longstring = join "", @examples;

print "\n", join ("\n",  
    $longstring =~ /(\$$RE{balanced}{-parens=>'{}'})/g);

__OUTPUT__

${ThisOne}
${This${One}}
${This${One}Too}
${This${One}and${also}this}

${ThisOne}
${This${One}}
${This${One}Too}
${This${One}and${also}this}
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