[fpc-devel] FPC Syntax

[Hans-Peter Diettrich]

A friend has found some obvious errors in the FPC syntax description,
and I found some more errors. Here is our current list:


====  ==================================================================
page  Expected Error Description
====  ==================================================================
p010:
      in
      characters:      ";"  is missing
      character pair   ".." is missing
========================================================================
p022:
      Where is delphi real type Currency
========================================================================
p041
      Normally a list of variables may be declared:
------------------------------------------------------------------------
      variable_declaration =
          list ":"
          type [ ("=" typed_constant) | variable modifiers ] ";" .
      --- should read ---
      variable_declaration =
          identifier_list ":"
          type [ ("=" typed_constant) | variable modifiers ] ";" .
      identifier_list =
        identifier { "," identifier} .
DoDi:
Should read like [ "=" typed_constant ] | [ variable_modifiers ]?
Should distinguish single variables, with possible modifiers,
	from variable list, with no(?) modifiers allowed?
========================================================================
p044:
      the word "property" is missing
      where is "stored" property
========================================================================
p048:
      "object_type" is missing in 1st description
========================================================================
p055
      class_reference_type
      "class_type" is missing
========================================================================
p072
     addressfactor
       should read
     address_factor
========================================================================
P069
      expression :   "*"   should read "<" .
========================================================================
p087
      formal parameter list
      may by empty
========================================================================
p101
      parameter_list
        should read
      formal_parameter_list
========================================================================
p108
      where is VAR  variable_declaration_part
========================================================================
p112
      where is "resident" in exports clause
========================================================================
p113
      where is "raise" in raise_statement
========================================================================
Sometimes:
  integerconstant:  p044, p059
  integer_constant: p095, p112
Missing:
    array_constant
    constant
    default_parameter_value
    exception_instance
    exception_statement
    integer_constant
    method_designator
    procedural_constant
    qualified_method_designator
    record_constant
Assumed:
address_expression =    expression .
address_constant =      expression .
class_type_identifier =      identifier .
constant_identifier =    identifier .
function_identifier =    identifier .
field_identifier =    identifier .
interface_type_identifier =   identifier .
integer_expression =    expression .
method_identifier =    identifier .
object_type_identifier =    identifier .
octal_digit =    "0".."7" .
parameter_type =    identifier .
procedure_identifier =    identifier .
qualified_method_identifier =   identifier { "." identifier } .
result_identifier =    identifier .
string_constant =    character_string .
string_constant_declaration =    identifier "=" character_string .
type_identifier =    identifier .
unit_identifier =    identifier .
variable =    identifier .
variable_identifier =    identifier .
variable_reference =    identifier .


DoDi:

p013
	"^"<letter> is missing as escaped character.

p015
	All <address constant> etc. should be described.
	(See above)

p017
	What about type: <identifier> "=" "type" <typedef>?
	(Delphi mode only?)

p020
	In enum types both "=" and ":=" are accepted.
(IMO ":=" could be removed here)

p079
	According to the examples the semicolon is a case
	delimiter/terminator, not a separator.
	The <else part> contains a <statement sequence>.
(The optional semicolon before "end" should be moved before "else").

The syntax of the Case statement has been seriously damaged by the
introduction of the Else part, this is a problem not only in the FPC
grammar. IMO the syntax diagram should be corrected, somehow, and the
quirks should be addressed in the comments.

p080:
What does this mean:
"The case statements can be compound statements (i.e. a begin..End
block)."
Do there exist cases where a compound statement can *not* replace a
statement?

About case and variant records:
Why is the syntax for Case labels different in Case statement and Record
types?
In the variant part of an record no ranges a..b are allowed. This IMO is
not a meaningful restriction, which requires different descriptions and
different handling in the compiler.


Should we continue to search for more errors?

DoDi