What is %_ for?

Since it's not documented in perlvar, I don't think it's for particular use. I think that FunkyMonk's reply is making sense. I also got the same impression upon reading about symbol table in perlmod and perlref.

If there is no current use, would anyone care to suggest what %_ might be used for?

Well, you can use it as you will normally use hash. Initialize it, assign elements to it, get a value from a key. Since it's sort, it's also perfect for golf. And it can also be confusing so one may use it in obfucasted code. You can use it to alias a hash variable with some lengthy you'd be tried to type it over and over. 

my %hash_variable_with_not_actually_that_long_name = (one => 1);
print $hash_variable_with_not_actually_that_long_name{one}, "\n";
*_ = \%hash_variable_with_not_actually_that_long_name;
print $_{one}, "\n";

# output
1
1

[download]
Additionally, with the aliasing, you can alias other sigils at once. But, by using _ you're likely to get into problem. 
$_ = 2;
print $_, "\n";
*_ = *hash_variable_with_no_actually_that_long_name;
print $_{one}, "\n";
print $_, "\n";

# output
2
1
(empty, with 'uninit' warnings under -w)

[download]

Open source softwares? Share and enjoy. Make profit from them if you can. Yet, share and enjoy!

In reply to Re: Does %_ have a function or is it just for fun? by naikonta
in thread Does %_ have a function or is it just for fun? by larard

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