Fix issues #49 and #50

[erihsu]

Hi, dalance Thanks for your great work on sv-parser, nice project. The pull request is trying to two issues opened by me. Changes are quite minor and these are just to support svfmt

1. sv-parser now can parse class definition now by add variant in Description enum, fix #50
2. sv-parser now can differentiate newline("\t") and space("\t" "\s"), fix #49

[dalance]

Thank you for your contribution. "2." seems to be good.

In SystemVerilog LRM, class_declaration is not allowd on the root of source code.

source_text ::= [ timeunits_declaration ] { description }
description ::=
module_declaration
| udp_declaration
| interface_declaration
| program_declaration
| package_declaration
| { attribute_instance } package_item
| { attribute_instance } bind_directive
| config_declaration

So the addtion of class_declaration seems to exceed the language standard. How about it?

[erihsu]

I agree with

So the addtion of class_declaration seems to exceed the language standard

As I have never fully read SystemVerilog LRM before, it's quite reasonable if LRM states the Description definition. Maybe I would later consider add formatting strategy without changing parser rule.

[erihsu]

Should I do something to trigger pull request merge ? I notice it's pended for nearly a month😂@dalance

[dalance]

I want to merge the change about whitespace. Could you remove the addition of class_declaration?

[erihsu]

Hi dalance, I have reverted changes in class declaration. Before that, I have thought you can personally pick partial commit from the pull request, never mind.

[dalance]

Thanks!