Dear monks, I need to consult your wisdom. Consider: 

use strict;

sub do_nothing { @_ }

my @in = qw( e n i g m a );

my @out = sort do_nothing( @in );

print "@out\n";

__END__

% perl enigma.pl
e n i g m a

[download]
To elucidate this puzzle, I consulted the inscrutably wise (though still fallible) -MO=Deparse: 
% perl -MO=Deparse enigma.pl
sub do_nothing {
    use strict 'refs';
    @_;
}
use strict 'refs';
my(@in) = ('e', 'n', 'i', 'g', 'm', 'a');
my(@out) = (sort do_nothing @in);
print "@out\n";
__DATA__

enigma.pl syntax OK

[download]
So perl is interpreting sort do_nothing( @in ) as sort do_nothing @in, which, given the explicit use of parentheses, seems to me beyond perverse.

Is this a bug or is this a feature?

the lowliest monk

In reply to Perversity of sorts by tlm

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