Hi all, I'm learning Perl (my only other programming experience is Tcl) and I'm having some trouble. I'm confused over lists, so I looked up some help and found this thread at Stack Overflow. I looked up the perldoc of reverse (reverse) and I on the page, there is some code, which I've slightly modified:

#!/usr/bin/perl
use strict;
use warnings;

print join(", ", reverse "world", "One"), "\n"; # One, world
print scalar reverse ("dlrow ,", "owT"),"\n";    # Two, world
 
$_ = "dlrow ,eerhT";
print reverse;                         # No output, list context
 
$_ = "dlrow ,ruoF";
print scalar reverse;                  # Four, world
[download]

I get the following output:

One, world
Two, world
Four, world
[download]

My first question is why isn't the third line printed? Reverse supposedly returns a list and the perldoc of print says that a list is one of it's arguments. Why doesn't this work? My second question is that if I explicitly state the $_ after reverse in the third print statement, then it prints out the string, but it is NOT reversed:

#!/usr/bin/perl
use strict;
use warnings;

print join(", ", reverse "world", "One"), "\n"; # One, world
print scalar reverse ("dlrow ,", "owT"),"\n";    # Two, world
 
$_ = "dlrow ,eerhT";
print reverse $_;                         # No output, list context
 
$_ = "dlrow ,ruoF";
print scalar reverse $_;                  # Four, world
[download]

I get the following output:

One, world
Two, world
dlrow, eerhTFour, world
[download]

What is going on here? Why does listing $_ explicitly as an argument to reverse cause print to work, but reverse() is not performed?

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