#!/usr/bin/perl -l

# http://perlmonks.org/?node_id=1139932

use strict;
use warnings;

my $in = 'text text {scope 4 text {scope 2 text {scope 1 text} scope 2 text} scope 4 text {scope 3 text} scope 4 text } text text';

print $_ = $in;

print while s/{[^{}]*}/PROCESSED/;