Re^4: RFC: "assignary" operator ?= :

> I like the compound operator x!!

It's a bit different than the if/else or ternary it's used to replace, though. Unlike them, the x!! evaluates the left hand side even if the condition is zero. Cf.

my $t;
sub tuple { $t++ => 12 }
my $bool = 0;
my %h = (tuple()) x !! $bool;
[download]

versus

...
my %h = $bool ? (tuple()) : ();
[download]

Now %h is the same, but $t is different.

map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

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Re^5: RFC: "assignary" operator ?= : by shmem (Chancellor) on Dec 08, 2019 at 21:03 UTC
It's a bit different than the if/else or ternary it's used to replace, though Ah no, this construct doesn't replace any ternary, it is a wholly different thing - but an example for replacement of a convoluted construct with a succinct idiom. Once you grok what `x!!` is about, you'll never forget what it does. perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'	[reply] [d/l]