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Thread-Topic: Array decomposition, more than list()
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Date: Sun, 13 May 2012 16:41:22 +0000
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Subject: Array decomposition, more than list()
From: cpriest@zerocue.com (Clint Priest)

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I've been using array decomposition in other languages such as Javascript r=
ecently and find it very useful.  I did not find any conversation about it =
in the archives, has this topic been discussed/vetted/shot down already?

Example use case: Indexed database results being iterated:

Input:
$tValues[$dbRow['ID1']][$dbRow['ID2']][$dbRow['ID3']] =3D $dbRow['Value'];

Output:
foreach($tValues as $ID1 =3D> $tSubValues1) {
    foreach($tSubValues1 as $ID2 =3D> $tSubValues2) {
        foreach($tSubValues2 as $ID3 =3D> $Value) {
            /* Do something, such as build an SQL insert */
        }
    }
}

The above is a semi-common piece of code in our production application, I c=
ould see list decomposition as a very convenient alternative.

New functionality would support:

foreach($tValues as $ID1 =3D> [$ID2 =3D> [$ID3 =3D> $Value] ]) {
    /* Do something */
}

The above also would indicate that associative array key decomposition woul=
d also be allowed.  I don't believe anything like the above is possible, ev=
en outside of a foreach loop, but perhaps I am wrong there.

What do you think?

-Clint

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