These functions deparse to two different lines:

@b = map(uc($_), @a);
print @b, "\n";
@b = map(uc($_), @a);
print @b, "\n";
@b = map(uc($_), @a);
print @b, "\n";
@b = map(uc($_), @a);
print @b, "\n";
@b = map({uc $_;} @a);
print @b, "\n";
@b = map({uc $_;} @a);
print @b, "\n";
@b = map({uc $_;} @a);
print @b, "\n";
@b = map({uc $_;} @a);
print @b, "\n";
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But these probably are interpreted in a next stage to exactly the same internally. So that's probably why the other people in this thread didn't find any realy difference with BenchMark.

Jeroen
"We are not alone"(FZ)