IPC using react/whenever

child-proc.py

#!/usr/bin/env python3

while 1:
    x = input('')
    if x == 'exit':
        print('exiting...')
        break
    print(x)

output.txt

pid: 22812
inside
outside
exiting...

parent-proc.p6

#!/usr/bin/env perl6
use v6;

my $isready = False;
my $proc = Proc::Async.new: 'python3', 'child-proc.py', :w;

start react {
    whenever $proc.Supply.lines { put $_ }
    whenever $proc.ready { say "pid: $_"; $isready = True; }
    whenever $proc.start {}
    $proc.put: 'inside';
}

until $isready {};
$proc.put: 'outside';
$proc.put: 'exit';
sleep 1;

[23:22] ryn1x: instead of whenever $proc.Supply.lines I think you can do just whenever $proc
[23:22] ah
[23:22] actually
[23:22] whenever $proc.lines ?
[23:22] ↑ that's the one, I think

[23:23] ryn1x: instead of until $isready {};
[23:23] use await $proc.ready