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Date: Sun, 12 Apr 2020 22:16:02 +0200
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To: PHP internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] [DISCUSSION] Match expression
From: tovilo.ilija@gmail.com (Ilija Tovilo)

Hi Rowan

> Can match arms contain other flow control, such as "return" or "continue"?

Yes and yes. They behave exactly the same as in the switch. This
should definitely be described in the RFC.

> Can I mix a bare value and a block as arms of the same match, or does the whole construct need to be in either "expression form" or "statement form"?

Yes, you can mix blocks and expressions given you don't use the return
value of the whole match expression.

> Can I omit the trailing semicolon even in "expression form"

Yes. To clarify what's going on here: There's no statement variant of
the match expression. PHP already allows using any expression as a
statement.
https://github.com/php/php-src/blob/422c8390a01ce9b6f612e0183bd0e4500c0608be/Zend/zend_language_parser.y#L446

That's why you can do something like `10 + 20;`. PHP will just discard
the result value. The same thing is happening here. The only
difference is that I added a rule to the grammar to allow dropping the
semicolon in this case because I noticed that I kept forgetting to add
it in my tests.

> We can always add statement blocks in later

I think we'll never completely agree on this point, and that's fine.
As mentioned in my announcement IMO it doesn't make sense criticizing
the switch statement but then not offering an alternative.

Thanks for your input!

Ilija