Hello all!

Starting this week, I will post the milestones for #SAOC2020 only on this thread, as it will be easier to follow them this way.

General milestones: [0].
Milestone 1 Update 1: [1].
Milestone 1 Update 2: [2].

My plan for last week was:
- to continue familiarizing myself with the M4 functions used within the repo (working on lookahead correction and continuing the add other features); (done)
- to start analyzing the C and C++ existing parsers, by writing programs that would help me understand the key differences between them. (not done - postponed)

As of last week:
- I continued to do tasks in the repo[3][4][5][6].
- Bison's documentation was updated to include D support[7]. I now have an updated list of the features in the D backend and I know what needs to be added or improved.
- I documented myself about some of the features I need to implement or improve asap (lookahead, error messages, etc).
- The PR[8] for dlang/phobos is still open.

The plan for next week:
- While finishing the documentation, I realized that the LALR parser has a lot of missing features, so I will focus on adding them.
- I also plan to enhance the user interface, allowing the user to view the TokenKind and the semantic value as a complete symbol, as opposed to different values.
- I will create a context error message function, that will help me better encapsulate the code, provide more efficient code (it will appear in the program only if certain directives have been selected by the user), and will make a smoother transition to adding the missing custom error message.
- I will also continue working on the lookahead correction if I have the time. It is postponed until I add the context functionality.

[0]: https://forum.dlang.org/post/ngdkxwyhrcduspuslfoe@forum.dlang.org
[1]: https://forum.dlang.org/post/xxnwpbmagtzuhwmsusnu@forum.dlang.org
[2]: https://forum.dlang.org/post/qnrnrjxrcmglbgwndkby@forum.dlang.org
[3]: https://github.com/akimd/bison/commit/4bbda69f1ef10a40cfd28deb9bf619e28dcdbf6b
[4]: https://github.com/akimd/bison/commit/4855b9855465c3289f1f8f452bc0b09ba5711e05
[5]: https://github.com/akimd/bison/commit/3829bd6262ee22f445217808dd0aa2c34b72f660
[6]: https://github.com/akimd/bison/commit/7cd195b30aa615fa9996f471c1f200e016a904a5
[7]: https://github.com/akimd/bison/commit/72360b51a545a5c1d03027885466f5855c67c61e
[8]: https://github.com/dlang/phobos/pull/7642

On Tuesday, 6 October 2020 at 20:31:41 UTC, Adela Vais wrote:
> [...]

Hello!

As of last week:
- The complete symbols and the custom error message functionalities are works in progress.
- The PR[0] for dlang/phobos is still open.

The plan for next week:
- Continue working on the above tasks.
- Add the lookahead correction if I have the time. It is postponed until I add the context functionality.

#SAOC2020

[0]: https://github.com/dlang/phobos/pull/7642

On Sunday, 18 October 2020 at 15:48:13 UTC, Adela Vais wrote:
>> [...]

Hello!

As of last week:
- I finished the Context class, which is providing information about the error token, its location, and the expected tokens. It is currently under review. [0]
- I implemented the custom error message functionality. It is currently under review. [0]
- I almost finished the lookahead correction feature, I expect it to be ready by the next update. [1]
- I made the requested changes for the PR for dlang/phobos. [2]

The plan for next week:
- Continue working on lookahead correction.
- Add tests for programs that use multiple parsers.
- Implement yyerrok, which is a way to make the parser resume to normal execution immediately after it encountered an error. [3]

#SAOC2020

[0]: https://github.com/akimd/bison/compare/master...adelavais:custom-error-message-squash
[1]: https://github.com/akimd/bison/compare/master...adelavais:add-lac
[2]: https://github.com/dlang/phobos/pull/7642
[3]: https://www.gnu.org/software/bison/manual/bison.html#Error-Recovery

On Monday, 26 October 2020 at 19:11:27 UTC, Adela Vais wrote:
>>> [...]

Hello!

As of last week:
- I resubmitted the Context class and the custom error message patches with the needed corrections and suggestions. [0]
- I made the requested changes for the PR for dlang/phobos. [1]
- I implemented the yyerrok functionality, which is currently under review. [2]
- I made a style cleanup in the D examples, currently under review. [3]
- I worked on the tests for programs that use multiple parsers, but I still have some problems. The problem is about integrating the tests I made in the test suite. If I can't make it work today, I will send a PR with what I changed until now so I can get help.
- After the modifications in the parser, the lookahead is again a work in progress.

The plan for next week:
- Continue working on the above.
- Start working on the push parser[4] for D (right now, the LALR1 parser is of type pull).

#SAOC2020

[0] https://github.com/adelavais/bison/tree/fix-context-squash
[1] https://github.com/dlang/phobos/pull/7642
[2] https://github.com/adelavais/bison/tree/yyerrok
[3] https://github.com/adelavais/bison/tree/examples-stylefix
[4] https://www.gnu.org/software/bison/manual/html_node/Push-Decl.html#Push-Decl

On Friday, 6 November 2020 at 16:08:55 UTC, Adela Vais wrote:
>>>> [...]
I forgot to modify the title of the last post, it was a status report for #SAOC2020 Milestone 2 Update 2.

On Friday, 6 November 2020 at 16:11:14 UTC, Adela Vais wrote:
>>>>> [...]

Hello!

As of last week:
- The patches sent last week were all accepted.
- I started working on internationalization, which allows the user to have the error messages translated in other languages. [1]
- The PR from Phobos is about to get merged (72h no objection -> merge label). [2]
- I have a fully working version of complete external symbols [3], but I need feedback from the D community to decide if this should replace the current code version or if both versions should be supported. I opened a discussion thread. [4]
- I started reading the documentation and analyzing the push parser code from the Java parser.

The plan for next week:
- Continue working on the above.

#SAOC2020

[1] https://github.com/adelavais/bison/tree/internationalisation
[2] https://github.com/dlang/phobos/pull/7642
[3] https://github.com/adelavais/bison/tree/complete-external-symbols
[4] https://forum.dlang.org/post/afiyfqqcauxdrbkrizri@forum.dlang.org

On Saturday, 14 November 2020 at 16:03:48 UTC, Adela Vais wrote:
>[...]

Hello!

As of last week:
- I added support for lookahead correction [1].
- I changed the return value of yylex() from TokenKind to YYParser.Symbol [2], and changed the YYLocation's type from class to struct [3], based on the feedback I received [4].
- I wrote a fix regarding the name of the custom error message function from the API [5].
- The PR from dlang/phobos was merged [6].
- The internationalization feature is a work in progress.

The plan for next week:
- Continue working on internationalization.
- Start coding the push parser.

#SAOC2020

[1]: https://github.com/akimd/bison/commit/593724366f714e6c0316c51716cc507309ea9030
[2]: https://github.com/akimd/bison/commit/10305f3e941591f1f915402f1c1076024129e624
[3]: https://github.com/akimd/bison/commit/e5854bbddd10d6b834622dc1e6b67c91b9c43f48
[4]: https://forum.dlang.org/post/mailman.6687.1605555766.31109.digitalmars-d@puremagic.com
[5]: https://github.com/akimd/bison/commit/0e51f6146ad32126b9fce26fb8de34c3d2f727e6
[6]: https://github.com/dlang/phobos/pull/7642

On Saturday, 21 November 2020 at 21:46:08 UTC, Adela Vais wrote:
>>[...]

Hello!

As of last week:
- I worked on internationalization. I changed my approach and moved to a code version more similar to the C parser's one. The code seems to be working, but I have some problems with the automatization of the testing process. I sent a WIP[1] for feedback.
- I opened a PR[2] in druntime to add libintl.h in the language, as it is often used with locale.h, and it would bring internationalization into D. At the moment, for internationalization, I am using functions from libintl.h and from locale.h (that exists in D, in core.stdc.locale). For the libintl functions, I am using extern(C).
- I started working on the push parser. At the moment, I am still working on a pull version, and I am extracting parse() local variables and making them members of the YYParser class. I do this to preserve the parser state between calls when I will move to a push parser.

The plan for next week:
- continue working on the above.

#SAOC2020

[1]: https://github.com/adelavais/bison/tree/internationalisation-gettext
[2]: https://github.com/dlang/druntime/pull/3300

On Wednesday, 2 December 2020 at 00:36:20 UTC, Adela Vais wrote:
>>>[...]

Hello!

As of last week:
- As libint.h is not a standard C header, it can't be added to druntime, so I will not be pursuing my PR[1] anymore. I started working on a dub package [2] instead.
- I fixed my setup and now internationalisation works as expected on my system. I sent a patch [3] and, after review, I need to make some changes before it is accepted.
- I started working on some old fixes that were requested [4]: style fixes in LALR1 and the documentation, creating an alias for the return value of yylex (now YYParser.Symbol can be referred to as Symbol) and reducing the verbosity of handling the location reporting in the examples and tests.
- The Lexer's return value is the Symbol struct. It receives the external token (TokenKind) and transforms it to its internal form (SymbolKind), saving only the latter. The parser had 2 variables, for both forms. I removed the variable for the external token [4], as there was no use for it anymore.

The plan for next week:
- From now until the end of #SAOC2020 I will work in parallel on the GLR and the remaining tasks from the LALR1, as the user interface (which is the same for both parsers) is almost finished.
- I will start working on the GLR, first by analyzing the already existing GLRs (in C and C++) and writing programs that would help me understand the differences between them and LALR1.
- I will add type aliases for a few internal types. The documentation specifies that the user should not use objects for which the name starts with "YY", as they are internal implementation details, and the examples use such objects/types (struct YYLocation, for example), which should be available for the user.

[1]: https://github.com/dlang/druntime/pull/3300
[2]: https://github.com/adelavais/libint
[3]: https://github.com/adelavais/bison/tree/internationalisation-squash
[4]: https://github.com/adelavais/bison/tree/fixes-from-changing-yylex-retval

On Thursday, 10 December 2020 at 23:44:13 UTC, Adela Vais wrote:
>>>>[...]

Hello!

As of last week:
- I added type aliases for location, position and semantic value, and sent the patches [1] for review.
- I used the existing C examples from the repo and started analyzing the code of the GLR, noting how the values progressed (and differed from the LALR1) throughout the parsing.

The plan for the next update:
- Continue analyzing the GLRs. After I feel confident enough that I understand C's GLR, I will move to the "old" C++ GLR, which is a wrapper around the C one.
- Fix the internationalisation patch.

#SAOC2020

[1] https://github.com/adelavais/bison/tree/fixes-from-changing-yylex-retval