perl5i project explains itself as “Perl 5 has a lot of warts, fix as much of it as possible in one pragma”. You can run your scripts with it by including perl5i (ie, use perl5i;). Best part is, it can be run at commandline with $ perl5i -e .
perl5i includes Autobox module which lets you call methods on primitive datatypes such as scalars and arrays (eg. “hello world”->print). This feature allows constructing very compact one-liners as shown below:
perl5i -e 'my @arr = ( 1 .. 10 ); @arr->map(sub {$_ ** 4 })->grep(sub { $_ > 3 })->sum->say'
Explanation: calculate to the 4th power for each element of @arr. Of those 4th power numbers, filter out the ones smaller than 3. Then sum up the new array and print the result.
perl5i -e 'my @test=(1,2,3,4); my @compare=(2,4,6); @test->intersect(\@compare)->size->concat("\t")->print'
Explanation: Find the intersection of two arrays (assigned to new array) and add tab character to size of (intersection) array and then print it.
perl5i -e ' my $hashref = { foo => 10, bar => 20, baz => 30, quux => 40 }; $hashref->values->sort->join("-")->say'
Explanation: sort the values of hash and print them by joining with “-” character.
