[Purdue-pm] TIL

[Dave Jacoby]

use JSON;
use PerlX::Maybe qw{ maybe provided };

my $json = JSON->new->canonical;

for my $i ( 1 .. 5 ) {
    my $x;
    $x = 1 if int rand 2;
    my $data = { maybe x1 => $x, x2 => $x, provided $i > 3, i => $i, };
    say $json->encode($data);
}

$ ./maybe.pl
{"x1":1,"x2":1}
{"x1":1,"x2":1}
{"x2":null}
{"i":4,"x1":1,"x2":1}
{"i":5,"x2":null}

x1 will always be a thing, but the value will be undefined half the time.

x2 will not be assigned unless the value it it defined exists. we get this
from `maybe`.

This is roughly

if ( defined $x ) { $data->{x2} = $x }

but so much more concise.

`provided` gives us conditionals.

if ( $i > 3 ) { $data->{$i} = $i }

becomes

provided $i > $3 , i => $i

it's small, among the smallest things thrown at me recently, but if nothing
else, it makes a smaller JSON string when used.

-- 
Dave Jacoby
jacoby.david at gmail.com

I deal with my software the way I treat my eldritch abomination:
 It's not human, it's not even alive in the natural sense.
 It's nightmare-born and nightmare-shaped, and nightmares don't die easy.
  -- @yenzie
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