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Date: Tue, 23 Feb 2021 19:05:47 +0000
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Subject: Re: [PHP-DEV] Inline conditional that returns null if falsy
From: rowan.collins@gmail.com (Rowan Tommins)

On 23/02/2021 18:41, Albert Casademont wrote:
> Sure, it's not a big deal having to write the ": null" but it doesn't add
> any value


On the contrary, it adds an important piece of information: that the 
default value is "null", rather than "false", or "0", or "new EmptyValue()".

For instance, it doesn't seem at all obvious to me that this code should 
produce a null:

$items = [];
$itemCount = $items ? count($items);

I might be more convinced that "null" is the "natural" value if the 
left-hand operand was only checked against null, not "falsiness": in 
that case, you can read it as "if it's null, leave it alone". I'd still 
be inclined towards "too specific to use up more syntax", though.



> A better example would creating UUID VO's from string|null
> input, there's little room for a default here.


I'm not quite sure what process you're describing, but any of the 
following seem equally reasonable:

$nullableUuid = is_null($input) ? UUID::for($input) : null;
$maybeNilUuid = is_null($input) ? UUID::for($input) : UUID:nilValue();
$definitelyUuid = is_null($input) ? UUID::for($input) : UUID:random();


Syntax for skipping the is_null/isset on the left would be higher up my 
wish list than syntax for skipping the :null on the right.


Regards,

-- 
Rowan Tommins
[IMSoP]