Grammar – Consistency & Cleanup 3

[Nigel-Ecma]

[Continues on from #1291 Grammar – Consistency & Cleanup 2]

This PR makes to small minor changes to the grammar, first it removes the unnecessary type_arguments, changing:

    type_argument_list
        : '<' type_arguments '>'
        ;
    
    type_arguments
        : type_argument (',' type_argument)*
        ;

to the more direct:

    type_argument_list
        : '<' type_argument (',' type_argument)* '>'
        ;

Second it moves the optional trailing comma on attribute into the list, changing:

    global_attribute_section
        : '[' global_attribute_target_specifier attribute_list ']'
        | '[' global_attribute_target_specifier attribute_list ',' ']'
        ;
    
    attribute_section
        : '[' attribute_target_specifier? attribute_list ']'
        | '[' attribute_target_specifier? attribute_list ',' ']'
        ;
    
    attribute_list
        : attribute (',' attribute)*

to the simpler:

    global_attribute_section
        : '[' global_attribute_target_specifier attribute_list ']'
        ;
    
    attribute_section
        : '[' attribute_target_specifier? attribute_list ']'
        ;
    
    attribute_list
        : attribute (',' attribute)* ','?

This has the advantage that the trailing comma is now part of the list and not a level
above, and simplifies the first two by removing the overlapping alternatives.

No text changes are required to support these grammar improvements.

This PR also updates the grammar checker framework to v2.3.2, which includes an improved
implementation of C#’s semantic rules for declaration_expression. For the details see its repo.

Review Notes:

You only need to consider the changes to the *.md files in standard; the other files are machine-generated updates to parsing test samples describing the new expected parse for some samples. If you wish to see visualisations of the changes you may download the changed *.svg files in the PR and the current versions of them in draft-v8 and view them side-by-side (multiple monitors helps!)

[BillWagner]

Thanks again @Nigel-Ecma

I like the progress. This looks great.

[jskeet]

Yup, looks good to me.

[BillWagner]

Merging this so @Nigel-Ecma can continue with grammar updates.