Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:92416
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: error (pb1.pair.com: domain garfieldtech.com from 66.111.4.26 cause and error)
To: internals@lists.php.net
References: <D33531D4.6D3F3%fsb@thefsb.org>
 <CAFMT4NqGa=mKUksczpe6HepjM1Wthsw9dY7dX3JBWO9xB-FLJA@mail.gmail.com>
 <D3357498.6D41E%fsb@thefsb.org>
 <CAFMT4NrN=q1ZBUXGBPquFTVVaJpoHfbhTDKU2LMZY1C5tu4FKg@mail.gmail.com>
 <D335A5AA.6D579%fsb@thefsb.org> <57103A46.6040803@garfieldtech.com>
 <CAFMT4NpOCf3VON01_3n4xMKVOhEVNL-CsRm5gYOgogEnwt=XvQ@mail.gmail.com>
 <5710BA79.5060108@lsces.co.uk> <57110DC5.8000007@garfieldtech.com>
 <571338E6.50507@fleshgrinder.com> <57145AF7.7060607@garfieldtech.com>
 <57149405.2040701@lsces.co.uk>
Message-ID: <57151210.7040704@garfieldtech.com>
Date: Mon, 18 Apr 2016 11:57:52 -0500
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:38.0)
 Gecko/20100101 Thunderbird/38.0.1
MIME-Version: 1.0
In-Reply-To: <57149405.2040701@lsces.co.uk>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 7bit
Subject: Re: [PHP-DEV] [RFC] Nullable Return Type Declaration
From: larry@garfieldtech.com (Larry Garfield)

On 4/18/16 3:00 AM, Lester Caine wrote:
> On 18/04/16 04:56, Larry Garfield wrote:
>> 2) Doesn't make it quite so easy, which hopefully discourages (but does
>> not prohibit) its usage.
> This implies that using 'null' is wrong ... and is a slippery slope to
> then 'disabling' null where some people think it should be removed. If
> PHP development is making these sort of decisions it should be clear
> that is the intention, not just 'hopefully discourages' things that some
> people have no appreciation of the usefulness of!

I am not sure what you're implying by "some people have no appreciation 
of the usefulness of"... I am well aware of NULL's use cases.  I am also 
well aware that the general zeitgeist in the language development 
community is that they're dangerous; the designer of the first language 
to have them calls them a "billion dollar mistake", many languages 
actively avoid having NULL in favor of something deliberately more 
structured.  NULLs are a very common cause of avoidable fatal errors in 
many languages (including PHP). NULLs are rude to users of your API, as 
it balloons the error handling code they need to deal with.

I am on record and will continue to be on record that null is *usually* 
wrong.  I consider that position entirely justified, as does the 
academic CS community.  I am also now on record suggesting that we use 
union types to allow type-or-null returns/parameters, which you're 
welcome to quote me on. :-)

Are you comfortable with the compromise position I've proposed?

-- 
--Larry Garfield