Rakudo does not support autorun. There $OUTPUT_AUTOFLUSHis a note in the 5to6-perlvar entry .
Some examples from ancient times mention the method autoflush, but this has disappeared:
$*ERR.autoflush = True;
$*ERR.say: "1. This is an error";
$*OUT.say: "2. This is standard out";
But this does not work:
There is no such "autoflush" method for invocant like "IO :: Handle"
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