You can declare an entity, but not a member of an entity. This is what the syntax error is about. In your bad case, you tried to declare my @hash{@keyarray}, which is an element of an entity.

It is NOT about the fact that you combined a declaration with an assignment.

This is fine: 
my $a = 1;

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and this is not fine: 
my $a[1];

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This is also no good: 
my @a; # this is okay
my $a[1];# no good

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In reply to Re: Complicated Hash Construction. by pg
in thread Complicated Hash Construction. by coolmichael

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