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Comment by hendrik-xdest | Hacker News Reader

Great work. Hope to see this evolve into a great little toolset.

I have gone through your code a bit and think that you should consider error handling first. Some methods return strings on error but arrays on success but this is not validated before using the value as an array (this results in the error reported before). I guess when no caching system is available the Dummy will break your code as well as it only returns false.

Also, I think using "False" instead of "false" results in two internal checks when PHP tries to determine if something is false or true, instead of one. Not sure if that is still the case with the latest PHP version, though. I reckon using "false" would be better.

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Thanks, and I agree. I usually use exceptions but for some things (like cache misses) it seems unwieldy. For the example of the cache calls, I check when I've done a cache call like:

$data = $cache->get("key");

if(!$data) { // do the stuff if cache misses }

Though yes, I do need to go through and make sure it's extremely robust, as I did hack it up in an evening :)

Y U NO USE your cache like that:

  $data = $cache->get('key',function() {
    // do the stuff if cache misses
    return $some_value_to_be_cached;
  });

? It's quite handy and it forces you to separate actual logic to get the value, which is good by itself.

That's a cool idea, but I wouldn't want to lose the scope as you would with a closure. I will look into seeing if it's possible, though.

Yep, but i you can call "loosing the scope" as "specifying data dependencies explicitly" :) It all depends on a use case, though.

I was thinking about the part where you check the cache with if (!$found)

On that note, I adapted a rule of an open source project (can't quite remember which) that said to never use !$var to validate your data. One should always use isset($found['args']) or empty($found['args']) or for example is_array($found) && count($found) > 0 to check.

I suppose I could use $var === False, to prevent it pick up empty results.

I've been burnt by this in the past. Nowadays I use ($found === false) to check for a cache miss (though this means you can't store boolean values verbatim).

This is why:

!array() -> true

!null -> true

!false -> true

!0 -> true

!"0" -> true (!!?)

!"" -> true

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