Consistently use php opening tag

[ravage84]

Which is mandated by 3. Declare Statements, Namespace, and Import Statements, anyway.

Kinda "eat your own dog food".

Plus, it makes it even more clear in what file type context the code examples are.

Lastly, this also fixes thie following oddly looking (and unnecessary) whitespace in 7.1 Short Closures:

[Crell]

I don't think this really applies here. I almost never see the PHP opening tags in markdown code blocks. The intent of the referenced section is that in a file you must start with the open tag, and use the long-tag version. That doesn't really apply to code snippets.

Leaving this open to see if anyone else on the team disagrees, but I'm voting won't-fix here.

[Crell]

(The unnecessary extra line in that one code block can be fixed in a separate PR.)

[mbniebergall]

Including the opening PHP tag <?php is not standard for code snippets. See examples of no opening PHP tags at:

• https://www.php-fig.org/psr/psr-15/
• https://www.php-fig.org/psr/psr-17/
• https://www.php-fig.org/psr/psr-18/

Some PSrs do include the opening tag, when conveying the context of the file, as seen in:

• https://www.php-fig.org/psr/psr-3/
• https://www.php-fig.org/psr/psr-20/#21-clockinterface

[alekitto]

I agree that the opening tag should not be mandatory for code snippets.
At the same time, I can see the inconsistency between the various PSRs: for example in PSR-3, the code block containing the interpolate function has an unnecessary opening tag, while the interface declarations (which are entire files) correctly have it.

I’m voting for wont-fix here, but probably we should define a general rule for code blocks/snippets

[KorvinSzanto]

I don't see value in including the PHP tag in code snippets unless the snippet encompasses the entire file so I agree this isn't something we should do.

[samdark]

I agree that there's no sense in adding it in these cases.

[ravage84]

(The unnecessary extra line in that one code block can be fixed in a separate PR.)

Separate PR: #80

[ravage84]

[...] At the same time, I can see the inconsistency between the various PSRs: for example in PSR-3, the code block containing the interpolate function has an unnecessary opening tag, while the interface declarations (which are entire files) correctly have it.

Actually, I disagree on that specific one because it could be the full code of this file., as well.
Adding a php opening tag implicitly hints at that & frames the whole code.

https://www.php-fig.org/psr/psr-3/#12-message

This would be a prime example where I would expect the php opening tag

[ravage84]

While I like the consistency of having opening tags everywhere, I can see it being "too much", especially for one liners.

What do you think of the alternative in #81?