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Date: Mon, 2 Feb 2015 19:41:38 +0100
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Subject: AW: [PHP-DEV] What do we need strict scalar type hints for?
From: php@tutteli.ch ("Robert Stoll")

Hi Dimitry,

> -----Urspr=C3=BCngliche Nachricht-----
> Von: Dmitry Stogov [mailto:dmitry@zend.com]
> Gesendet: Montag, 2. Februar 2015 10:13
> An: PHP Internals; Andrea Faulds; Nikita Popov
> Betreff: [PHP-DEV] What do we need strict scalar type hints for?
>=20
> hi,
>=20
> could you please write down few use cases, when strict scalar type =
hints are really useful.
>=20
> Thanks. Dmitry.

I think strict types are beneficial in all those places where you would =
put manual tests to ensure that the passed value is of a certain type =
and only of this type - removing the hassle (ok, I did not add anything =
to the discussion so far ^^). Right now, I mainly think of functions =
which expect an int - especially in the domain of time and money.  I =
would expect an int and I would not want that a float can be passed =
without warning and get silently converted to an int (loosing precision =
in the domain of time or money can be crucial).=20

However, IMO it is not necessary to have a strict mode as presented by =
Andrea -- I think it would be good enough if we use the same widening =
rules as in Java, C# etc. and be strict otherwise. I am aware of that =
with the support of BigInteger we would have a widening problem =
(BigInteger to float) but could be solved by a BigDecimal as in Clojure.

Ah... I now something I would definitely want to be strict. I guess a =
typical bug, which is made by many beginners, is using the result of =
strpos in an if statement without using the identity operator -- btw. =
would the strict mode affect operators and control structures as well? =
Would somehow be the logical consequence but I suppose the impact on =
performance would be too big. Or wouldn't it?
Back to the topic, if I expect a bool as parameter I would definitely =
not want it to be automatically converted since this is a sink for bugs. =


Hope that helps.

Cheers,
Robert