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Comment by Wilya | Hacker News Reader

It's funny. I don't have much experience with php, and I had to actually run your last example to know that it appended the values (instead of recreating the array with a single value each time).

Is there an append operator, or something more explicit ? '+=' seems to do something strange..

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Not sure exactly what you were trying. Using the [] syntax is common for appending elements (using the next available key). Otherwise you can use the array functions (array_push/pop/etc). As for plain operators, here is how PHP handles array operators: http://www.php.net/manual/en/language.operators.array.php

[] IS the append operator. And += only works right if both sides are arrays. If not the right side will be converted. += is really intended for hashmaps, not integer indexes, for those use [].

+= does union-by-key: any keys present in the right array, and not in the left, are appended to the left.

`array_merge` will append all numeric keys from the right array to the left, under new key values, as if you used [] one-by-one; for string keys, all keys from the right are copied into the left, possibly overwriting what was there.

In real code, I either have all-numeric or all-string keys, and `array_merge` does what I want in bulk operations: it's essentially equal to Python list.extend and dict.update, respectively. `+` on arrays is basically useless for me.

If you want something more explicit you probably want array_push($array,$val1,$val2,$val....);

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