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