Only add PHP opening tag when the following rule of thumb are met

[ravage84]

While I like the consistency of having opening tags everywhere (as in #74), I can see it being "too much", especially for one liners.

What do you think of the following rule of thumb proposal?

Add PHP opening tags when all requirements are met:

• Tne mandatory class namespace is defined or no class or interface respectively is defined
• All necessary classes & functions are imported
• All necessary variables & constants are defined
• All necessary structures are visible or hinted at with a comment
• All statements and/or structures are related to each other
• Or the PHP opening tag is essential to the code example

Do not add PHP opening tags when:

• Only one or many unrelated statements are shown
• Only one or many unrelated functions are shown
• Only one or many unrelated methods are shown
• Only one or many unrelated classes or interfaces respectively are shown
• Only one or many unrelated other structures, such as an if-clause or match expression, are shown

[Crell]

I'd leave this one. We're talking about the use statements, which happen at a very specific place in the file, so I think it's fine to leave here.

[vjik]

Suggest shorten the list when need add PHP opening tag to several items:

• block contain code with several sections (for example, class declaration + use) that can be placed whole in file;
• the PHP opening tag is essential to the code example.

In otherwise cases <?php looks overhead.