object/stdClass confusion

[nikic]

Appendix A / Keywords says:

5.  'object', the element to which this type applies is the instance of an
    undetermined class.
    This could be considered an alias for providing the class stdClass, as this
    is the base class of all classes, but the intention of the type differs.

    Providing stdClass will imply the intention that the related element contains
    an actual object of class stdClass or direct descendant, whereas object
    implies that it is completely unknown of which class the contained
    object will be.

This is not correct. stdClass is not a common base class of all classes. There is no common case class in PHP.

[nikic]

Another small mistake:

* "DocComment" is a special type of comment which starts with `/**`, ends
  with `*/` and may contain any number of lines in between.
  When a DocComment spans multiple lines, every line SHOULD start with an
  asterisk that is aligned with the first asterisk of the opening clause.

  In case a DocComment spans multiple lines then every line should start with
  an asterisk (`*`) that is aligned with the first asterisk of the opening
  clause.

The last sentence is duplicated there. Furthermore a "DocComment" starts with /** followed by a whitespace character (unless you intentionally deviate from PHP's definition here?)

[nikic]

Furthermore I'd suggest some changes to the Types ABNF. Current issues:

• type-expression can have trailing | (or lack it to separate types)
• array should be included in type (semantically)
• "array" should be in keyword
• class-name should allow any valid (literal) PHP class name
• class-name currently can't start with ""
• *1SP should presumably be 1*SP

Suggested wording:

type-expression  = type *("|" type)
type             = class-name / keyword / array
array            = (type / array-expression) "[]" / generic
array-expression = "(" type-expression ")"
generic          = collection-type "<" [type-expression "," 1*SP] type-expression ">"
collection-type  = class-name / "array"
class-name       = ["\"] label *("\" label)
label            = (ALPHA / %x7F-FF) *(ALPHA / DIGIT / %x7F-FF)
keyword          = "array" / "bool" / "boolean" / "callable" / "double" / "false" / "float" / "int" / "integer" 
keyword          =/ "mixed" / "null" / "object" / "resource" / "self" / "static" / "string" / "true" / "void"     
keyword          =/ "$this"

[mvriel]

You suggestion is an excellent improvement to the ABNF, thank you. I have made one modification: the 1*SP has been replaced with *SP to allow omitting a whitespace (I wouldn't recommend it but I think it shouldn't be disallowed)