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Comment by Minor49er | Hacker News Reader

The Match Expression feature is interesting. According to the PHP docs, it can even handle non-identity expression, although the approach seems a little hacky:

https://www.php.net/manual/en/control-structures.match.php#e...

    <?php

    $age = 23;

    $result = match (true) {
        $age >= 65 => 'senior',
        $age >= 25 => 'adult',
        $age >= 18 => 'young adult',
        default => 'kid',
    };

The above example will output:

    string(11) "young adult"

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I use `match` like this a lot now, often with PHP 8.1's enums[1]. It makes it easy to write clean dynamic accessors, without all the extra blocks required with multiple `if` branches:

    /** Check the status of this Task instance. */
    public function status(): Status
    {
        return match (true) {
            $this->inProgress() || $this->isInReview() => Status::Started,
            $this->isApproved() || $this->isRejected() => Status::Finished,
            default                                    => Status::Planned,
        };
    }

[1] https://stitcher.io/blog/php-enums

I've seen the same hack done with `switch (true)` in pre-PHP8 code (and other languages) as well.

match is basically a cleaner, more succinct switch, I hardly ever used switches before, though I use match a LOT.

    switch ($i) {
      case 0:
        echo "i equals 0";
        break;
      case 1:
        echo "i equals 1";
        break;
      case 2:
        echo "i equals 2";
        break;
    }

verses:

    $output = match($i) {
       0 => 'i equals 0',
       1 => 'i equals 1',
       2 => 'i equals 2',
      default => 'i is unknown'
   }

   echo $output;

the result is basically the same, but match is more of an enclosed switch that just returns instead of does side effects, then you can do what you like w/ that.

Ymmv, but match is a great code saver, and is very nice for enums and methods on enums.

Before match i'd probably do something like:

    $output = 'i is unknown';

    if($i == 0){
        return 'i equals 0';
    }

    if($i == 1) {
        return 'i equals 1';
    }

    if ($i == 2) {
        return 'i equals 2';
    }
    return $output;

Not really, I'd probably do..

    if($i) {
        return "i equals {$i}";
    }
    return 'i is unknown';

but the point was if I had to check for multiples to match something, then do something else, that's how I would do it... albeit this is a simple case with a better solution.

What am I missing? Isn’t that the output that makes sense? Or am I misunderstanding your comment about it being hacky?

I think they're talking about the "match (true)".

You are correct. This is what I was referring to

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