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Date: Tue, 26 Apr 2022 15:16:00 +0200
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Subject: Re: [PHP-DEV] Stricter implicit boolean coercions
From: a.leathley@gmx.net (Andreas Leathley)

On 26.04.22 14:47, Christian Schneider wrote:
> There are two big reasons:
> - BC: Checking for the truthiness of a value is very common and would re=
quire a lot of code changes.
> - Some of us like the conciseness of "if ($foo) ...", see below

That would not be my target - in an if expression a lot more values are
allowed anyway (arrays, objects, etc.), so this is not about determining
truthiness, but actual conversions to a bool type, like a bool
parameter, a bool return type or a bool property type. The inspiration
for this is the "Deprecate implicit non-integer compatible float to int
conversions" (https://wiki.php.net/rfc/implicit-float-int-deprecate),
minus the mathematical expressions that were considered there. It is
about avoiding probably-unintended values being coerced to boolean and
therefore losing information / adding unnoticed bugs to a codebase.

> I'm definitely against adding more special cases like 'false'.
> Side-note: Removing something like '0' =3D> false is also a BC break, no=
t just adding 'false'.

I am not suggesting removing the coercion from the string '0' to false
or changing anything about that.

> One of the big issues I have with this (as well as undefined variables
> not being allowed in if ($foo)) is that the replacement constructs are
> clunky:
> 	if ($foo)  =3D>. if (!empty($foo))
>
> For me this is quite a regression in readability but then again that's a=
 matter of taste.
> And would !empty($foo) even work in your world or how would empty() be d=
efined?
empty is also not something I would consider covering, as there you also
do not need a conversion to a bool type.