Hmm, I meant this line of the OP's code:

I think it can be called an assignment to an array, which imposes a list context on the right-hand side, as it is described in perldata:

Assignment to a scalar evaluates the right-hand side in scalar context, while assignment to an array or hash evaluates the righthand side in list context. Assignment to a list (or slice, which is just a list anyway) also evaluates the righthand side in list context.

I think this would be an assignment to a list:

my ($num) = ...
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