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Numerically indexed arrays

When declaring arrays, a trailing space must be added after each comma delimiter to improve readability:

$myarray = [1, 2, 3, 'Stuff', 'Here'];

Multi-line indexed arrays are fine, but pad each successive lines as above with an 4-space indent:

$myarray = [1, 2, 3, 'Stuff', 'Here',

   $a, $b, $c, 56.44, $d, 500];

Note that the example above also can be written as follows:
(with special attention to the last line having a trailing comma to extend the list of items later with a cleaner diff)

$myarray = [

   1, 2, 3, 'Stuff', 'Here',
   $a, $b, $c, 56.44, $d, 500,

];

In any case, brackets and newlines need to be balanced, irrespectively of the number of elements per line.