Arguments to methods must be specified in parentheses when using the arrow notation. There's no way how to parse

$foo->mysub %2
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as a method call followed by a hash.

Interestingly, such a parse is possible in the indirect object notation:

method $obj %2
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nevertheless, Perl parses that as modulo, too:

perl -MO=Deparse,-p -e 'method $o 2; method $o %2'
$o->method(2);
($o->method % 2);
-e syntax OK
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