Add number labels to the BNF file for the grammar

[afs]

The BNF file does not have numeric labels for rules; the HTML table does.

Add number to the BNF text presentation for the grammar.

The numbering should line up with the HTML table.

Such numbering is may be not "strict" W3C EBNF but there again, nor are newlines inside rules.
Numbering is easy to remove.

(The BNF file is new in SPARQL 1.2)

Before:

QueryUnit                 ::= Query
Query                     ::= Prologue ( SelectQuery | ConstructQuery | DescribeQuery | AskQuery ) ValuesClause
UpdateUnit                ::= Update
Prologue                  ::= ( BaseDecl | PrefixDecl | VersionDecl )*
BaseDecl                  ::= 'BASE' IRIREF
PrefixDecl                ::= 'PREFIX' PNAME_NS IRIREF
. . .
PN_CHARS                  ::= PN_CHARS_U | '-' | [0-9] | #x00B7 | [#x0300-#x036F] | [#x203F-#x2040]
PN_PREFIX                 ::= PN_CHARS_BASE ((PN_CHARS|'.')* PN_CHARS)?
PN_LOCAL                  ::= (PN_CHARS_U | ':' | [0-9] | PLX ) ((PN_CHARS | '.' | ':' | PLX)* (PN_CHARS | ':' | PLX) )?
PLX                       ::= PERCENT | PN_LOCAL_ESC
PERCENT                   ::= '%' HEX HEX
HEX                       ::= [0-9] | [A-F] | [a-f]
PN_LOCAL_ESC              ::= '\' ( '_' | '~' | '.' | '-' | '!' | '$' | '&' | "'" | '(' | ')' | '*' | '+' | ',' | ';' | '=' | '/' | '?' | '#' | '@' | '%' )

After:

[1]    QueryUnit                 ::= Query
[2]    Query                     ::= Prologue ( SelectQuery | ConstructQuery | DescribeQuery | AskQuery ) ValuesClause
[3]    UpdateUnit                ::= Update
[4]    Prologue                  ::= ( BaseDecl | PrefixDecl | VersionDecl )*
[5]    BaseDecl                  ::= 'BASE' IRIREF
[6]    PrefixDecl                ::= 'PREFIX' PNAME_NS IRIREF
. . . 
[188]  PN_CHARS                  ::= PN_CHARS_U | '-' | [0-9] | #x00B7 | [#x0300-#x036F] | [#x203F-#x2040]
[189]  PN_PREFIX                 ::= PN_CHARS_BASE ((PN_CHARS|'.')* PN_CHARS)?
[190]  PN_LOCAL                  ::= (PN_CHARS_U | ':' | [0-9] | PLX ) ((PN_CHARS | '.' | ':' | PLX)* (PN_CHARS | ':' | PLX) )?
[191]  PLX                       ::= PERCENT | PN_LOCAL_ESC
[192]  PERCENT                   ::= '%' HEX HEX
[193]  HEX                       ::= [0-9] | [A-F] | [a-f]
[194]  PN_LOCAL_ESC              ::= '\' ( '_' | '~' | '.' | '-' | '!' | '$' | '&' | "'" | '(' | ')' | '*' | '+' | ',' | ';' | '=' | '/' | '?' | '#' | '@' | '%' )

[Tpt]

I am not sure of the added value. Rule numbers change each time we add a new rule so they are kind of "representational only" and should not be relied on.

[afs]

Yes, they might change.
The BNF and the in-document HTML will have the same numbering so it is a way to navigate between them.

Production names are not chosen with convenience in mind!