So you want to filter-in hash elements that have a defined value:

my %args = (profile => 'foo');
my %ta = map {defined($args{$_} ? ($_ => $args{$_}) : ()} qw(profile u
+ser password);
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If a map iteration returns an empty list, nothing gets added to the recipient's list. I don't usually like making map behave like grep, but in this case it seems a reasonable fit.

grep behavior can be provided by map by adding a Boolean test and a conditional return value.

my @array = grep {COND} LIST;
my @array = map {COND ? $_ : ()} LIST
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