If you just want to autovivify the hash keys without actually assigning any value, you can do that:

[0] Perl> @array = split /\s*/, 'the quick brown fox jumps over the la
+zy dog';;
[0] Perl> @hash{ @array } =( );;
[0] Perl> print sort keys %hash;;
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You can also do undef @hash{ @list }; which benchmarks very slightly faster.

Whether you think "people will be confused" by either of these is your own call, or that of your employer.