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Subject: Re: Array comparison works completely different than documented?
From: cmbecker69@gmx.de ("Christoph M. Becker")

On 01.12.2021 at 14:56, Andr=C3=A9 H=C3=A4nsel wrote:

> The official documentation contains a conceptual description of array
> comparison in
> https://www.php.net/manual/en/language.operators.comparison.php#example-=
113.
>
> Curiously the people who wrote the inofficial spec (I think the HHVM tea=
m at
> Facebook?) came to
> pretty much the same result, described in
> https://github.com/php/php-langspec/blob/master/spec/10-expressions.md#r=
elat
> ional-operators:
>
>> If both operands have array type, if the arrays have different numbers =
of
> elements, the one
>> with the fewer is considered less-than the other one, regardless of the
> keys and values in each,
>> and the comparison ends. For arrays having the same numbers of elements=
,
> the keys from the left
>> operand are considered one by one, if the next key in the left-hand
> operand exists in the
>> right-hand operand, the corresponding values are compared. If they are
> unequal, the array
>> containing the lesser value is considered less-than the other one, and =
the
> comparison ends;
>> otherwise, the process is repeated with the next element. If the next k=
ey
> in the left-hand
>> operand does not exist in the right-hand operand, the arrays cannot be
> compared and FALSE is
>> returned. If all the values are equal, then the arrays are considered
> equal.
>
> In reality, array comparison works completely different, it is however
> unclear to me how exactly
> it does work: https://3v4l.org/630vG

The point is that $a > $b is actually checking whether $b <=3D $a.  This
is fine for ordered values, but these arrays are not orderable
(according to PHP's comparison).  That might indeed not be documented in
the PHP manual (the language specification appears to be abandoned anyway)=
.

=2D-
Christoph M. Becker