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    $p = Acme::Parataxis->new(code => sub {
        for my $item (qw[Apple Banana Cherry]) {
            say "Producer: Sending $item";
            $c->transfer($item);
        }
        $c->transfer('DONE');
    });

    $c = Acme::Parataxis->new(code => sub {
        my $item = Acme::Parataxis->yield( ); # Initial wait
        while (1) {
            last if $item eq 'DONE';
            say "Consumer: Eating $item";
            $item = $p->transfer( );
        }
    });

    $c->call( ); # Prime consumer
    $p->call( ); # Start producer

=head1 BEST PRACTICES & GOTCHAS

=over

=item * B<Avoid blocking syscalls:> Never call blocking C<sleep( )> or C<sysread( )> on the main interpretation thread.
Always use the C<await_*> equivalents to offload work to the pool.

=item * B<Thread Safety:> While Perl code remains single-threaded, background tasks run on separate OS threads. Shared
C-level data (if accessed via FFI) must be mutex-protected.

=item * B<Stack Limits:> Each fiber is allocated a 512KB stack by default. This is more than sufficient for most
Perl code and allows for high concurrency with a small memory footprint. Extremely deep recursion or massive regex
backtracking might still hit limits.

=item * B<Efficiency:> The native thread pool is initialized dynamically upon the first asynchronous request. It
starts with a small "seed" pool and grows on demand up to the configured limit. Worker threads use condition
variables to sleep efficiently when idle, ensuring near-zero CPU usage when no background tasks are pending.

=item * B<Reference Cycles:> Be careful when passing fiber objects into their own closures, as this can create
memory leaks.

=back

=head1 GORY TECHNICAL DETAILS

=head2 Architectural Inspiration

The concurrency model in Parataxis is heavily inspired by the B<Wren> programming language, specifically its treatment
of fibers as the primary unit of execution and its deterministic cooperative scheduling.

=head2 Stack Virtualization

On Unix-like systems, we use C<ucontext.h> to manage stack and register state. On Windows, we leverage the native
C<Fiber API>. In both cases, we perform heart surgery on the Perl interpreter by manually teleporting its internal
global pointers (the C<PL_*> variables) between contexts.

=head2 Shared CVs and Pad Virtualization

A significant challenge in Perl green threads is the shared nature of PadLists and the global C<CvDEPTH> counter. In
debug builds of Perl, calling a shared subroutine from multiple fibers can trigger internal assertions (like
C<AvFILLp(av) == -1>). Parataxis includes a specialized workaround that surgically cleans the next landing pad before
every context switch to satisfy these assertions without clobbering active lexical state.

=head2 C<eval> vs. C<try/catch>

While C<feature 'try'> is available in modern Perl, manually teleporting interpreter state can occasionally confuse the
compiler's expectations for stack unwinding. Standard C<eval { ... }> remains the most predictable way to handle
exceptions within fibers.

=head2 Signal Handling

Signals are delivered to the main process thread. Perl handles these at 'safe points,' which in this module typically
occur during a context switch (yield, transfer, or call). If you send a signal while a fiber is suspended, it will
generally be processed when the fiber is resumed and hits the next internal Perl opcode.

=head2 The 'Final Transfer' Requirement

In a symmetric coroutine model (using C<transfer( )>), fibers don't have a natural 'parent' to return to. I've added
fallback logic to return to the C<last_sender> or the main thread on exit but it's good practice to explicitly
C<transfer( )> back to a partner fiber or the C<root( )> context to ensure your application logic remains predictable.
Leaving a fiber to just 'fall off the end' is like walking out of a room without closing the door; eventually, the
draft will bother someone.

=head2 C<is_done( )> vs. Destruction

A fiber being C<is_done( )> simply means its Perl code has finished executing. The underlying C-level memory (stacks,
context, etc.) is not immediately freed until the C<Acme::Parataxis> object is destroyed or the runtime performs its
final C<cleanup( )>. This is why you might see memory usage stay flat even after a fiber finishes, until the garbage
collector finally catches up with the object.

=head1 AUTHOR

Sanko Robinson <sanko@cpan.org>

=head1 LICENSE

Copyright (C) Sanko Robinson.

This library is free software; you can redistribute it and/or modify it under the terms found in the Artistic License
2.

=cut