#!/usr/bin/env perl
my $copyright = <<'COPYRIGHT';
# Copyright 2021 by Christian Jaeger <ch@christianjaeger.ch>
# Published under the same terms as perl itself
COPYRIGHT
use strict;
use utf8;
use warnings;
use warnings FATAL => 'uninitialized';
use experimental 'signatures';
use feature 'current_sub';    # __SUB__
my ($mydir, $myname);
BEGIN {
    $0 =~ /(.*?)([^\/]+)\z/s or die "?";
    ($mydir, $myname) = ($1, $2);
}
# Just some random stupid curried and partially self-recursive
# function:
sub foo($x) {
    sub ($y) {
        # warn "f called";
        my $f = __SUB__;
        sub ($z) {
            $z < 1000 ? $f->($x * $y)->($z + $y) : $z
        }
    }
}
# Now show that this doesn't leak:
sub t ($n) {
    my $res;
    for (1 .. $n) {
        $res = foo(50)->(30)->(30);
    }
    $res
}
warn
    "Please verify manually from outside (e.g. `top`) that this process, pid $$, doesn't increase memory usage over time";
my $res = t 10000000;
# use FP::Repl; repl;