I appreciate firming up a consensus on indentation styles but I want to be clearly -1 on a codebase-wide reformatting for the foreseeable future. Beyond the merges, we have active branches for older releases, the more reformatting we do, the harder back- and forward-porting becomes. I like the idea of being more consistent for future work and, where code is particularly crufty, refactoring before making a change. The "worst" formatted code in couchdb is generally the oldest, and much of that needs a refactor/rewrite as we get to it.
B. On 4 Apr 2014, at 14:07, Alexander Shorin <[email protected]> wrote: > Hi Joan and all, > > I just faced another indention case which left out of scope of the vote: > https://gist.github.com/kxepal/2c09fb5348ead90bea04 > > Personally, I'm for 1) variant there. > > Another interesting case is anonymous function: > https://gist.github.com/kxepal/c5480209af9e93a14155 > > I prefer 3) one. > > What would be your recommendations there about? > > -- > ,,,^..^,,, > > > On Fri, Apr 4, 2014 at 9:24 AM, Joan Touzet <[email protected]> wrote: >> Hi everyone, >> >> Time to summarize the results. You can view the results at >> >> https://docs.google.com/forms/d/1b7KcQGgNbSCZVRwLjrUl5Z6C2TBx8X1btlU5fwrNHpg/viewanalytics >> >> but I've included them in this email for ease of review. >> >> I'm going to break this up into sections and make some PROPOSALs. I'd >> like to get general consensus on this vs. a "lazy" approach. I don't >> see this as something where need a unanimous vote but I'd like to get us >> all agree on something we can live with. >> >> As for getting this into the code base - let's not endanger the big >> merges, but once we have finished them, we should move to these >> standards piecemeal as we rework each file, as Noah and Jan suggest, >> unless someone wants to do the busy work and re-indent everything. >> Hopefully, even with the wait for the merges, this means the standard >> can be "live" before the end of 2014 ;) >> >> I don't cover all topics in here - please feel free to follow the post's >> format and add additional proposals in follow-ups. >> >> Finally, if I say something you disagree with or if I have misinterpreted >> your response, speak up - it was not intentional! >> >> -Joan >> >> ----- >> >> TERMINOLOGY USED: >> * "X space indent" means X spaces from the LEFT MARGIN. >> It is the ABSOLUTE number of columns of whitespace on a line. >> >> * "Y space standard" means indentations should be multiples >> of Y spaces. >> >> * "Z level indent" means Z*Y=X absolute spaces for the indent. >> For a 4-space standard, a 2 level indent would mean an 8 space >> indent. >> >> ----- >> >> STANDARD: Agree on a 4-space standard for horiz. indentation. Most of >> the respondents seem to be comfortable with this, likely due to the >> prevalence of the Python / Ruby / JS 4-space standard. >> >> PROPOSAL: "Indent your code blocks with 4 spaces. Never use tabs or a >> mix of tabs and spaces. When additional indentation levels are needed, >> always increment by a multiple of 4 spaces." >> >> This sets us up to be able to have the same spacing standard across JS, >> C and other languages we may someday ship. >> >> ----- >> >> LINE LENGTH: 11 votes for 80, 6 votes for 132, 1 for 76. >> >> PROPOSAL: "Maximum line length is 80 characters, with a preference for >> 76 characters or less. Exception: URLs in comments" >> >> ----- >> >> CASE STATEMENT INDENTATION: 16 in favour of this format, 3 opposed: >> >> get_ini_files(Default) -> >> case init:get_argument(couch_ini) of >> error -> >> Default; >> {ok, [[]]} -> >> Default; >> {ok, [Values]} -> >> Values >> end. >> >> This format matches Erlang documentation and is fairly canonical. >> >> PROPOSAL: "Indent case pattern clauses 1 level, and each case pattern >> body 2 levels from the initial case statement." >> >> ----- >> >> CASE STATEMENT ONE-LINERS: 11 in favour, 8 opposed: >> >> case {Name, Pass} of >> {"Jan Lehnardt", "apple"} -> ok; >> ... >> >> The only write-in for this suggested that one-liners needed to fit on a >> single line "without looking terrible." >> >> PROPOSAL: "Generally, case pattern bodies should always start on a new >> line from their corresponding case pattern clause. However, you can put >> the clause and body on the same line if the entire statement fits on one >> line." >> >> This is a tough one because it directly contradicts the previous >> proposal. If people feel strongly I am OK to be more strict and remove >> "Generally, " and the second sentence from this proposal. >> >> ----- >> >> LONG FUNCTION CLAUSE: >> >> 7 for paren aligned >> 4 for 2-space indented >> 5 for 8-space indented >> 1 for "2 space, but no arguments on the initial line, with >> the closing } on its own line" >> 1 for "4-space indented" >> 1 for "one tab" >> >> As a reminder, here is the code, paren aligned: >> >> possibly_embed_doc(#collector{db_name=DbName, query_args=Args), >> #view_row{key=_Key, id=_Id, value=Value, doc=_Doc}=Row) -> >> >> And 8-space aligned: >> >> possibly_embed_doc( >> #collector{db_name=DbName, query_args=Args), >> #view_row{key=_Key, id=_Id, value=Value, doc=_Doc}=Row) -> >> >> >> Ideology here and on the list is split roughly into 2 camps: >> >> * Z-level indent of a multiple of 4 spaces. As the body of the >> function will start at 4 spaces, I am going to recommend >> against 1-level and say a 2-level (8 space) indent is the >> option here. >> >> * Emacs/paren indentation mode. I believe the big arguments for >> this mode is "it's what my editor does" and "it's common in >> strongly typed languages." If you feel differently, please >> speak up. On the other side, Paul feels strongly about not >> adopting this model; Wendall supports it and Bob N. says he >> can 'retrain himself' to use it. Notice also that, in this >> example, the second line ends on col. 78. Even if the -> was >> wrapped to the next line, the line still ends on col. 75. >> >> Tough call here. Based on similarity with other popular languages of our >> day I'm going to initially propose the first option and let anyone who >> strongly opposes speak up now. There was no strong statement >> about whether the ) or -> should be on its own line, so I'll leave >> that part of the proposal vague for now. >> >> PROPOSAL: "Function definitions should align wrapped elements using a >> 2-level hanging indent. There should be no arguments on the first line. >> The closing parenthesis or arrow may be placed on its own line if >> desired, but if so, it should be indented the same number of spaces as >> the function definition itself." **but see below** >> >> ----- >> >> LONG FUNCTION CALL: >> >> 7 for paren-aligned >> 7 for 4-space indent >> 3 for 8-space indent >> 1 for "rework the code, or 4-space indent" >> 1 for "2 space, but no arguments on the initial line, with >> the closing } on its own line" >> >> As a reminder, here is the code, paren-aligned: >> >> [_A, _B, _Cs] = re:split(?b2l(AuthSession), ":", >> [{return, list}, {parts, 3}]), >> >> And 8-space aligned: >> >> [_A, _B, _Cs] = re:split(?b2l(AuthSession), ":", >> [{return, list}, {parts, 3}]), >> >> The more I looked at this topic, the more it looked like the last one, >> but even more space constrained because of the existing indent of the >> call itself. As such I'm going to roll it into the previous proposal: >> >> REVISED PROPOSAL: "Function definitions *and calls* should align wrapped >> elements using a 2-level hanging indent. There should be no arguments on >> the first line. The closing parenthesis or arrow may be placed on its >> own line if desired, but if so, it should be indented the same number of >> spaces as the function definition or call itself." >> >> That means these would be acceptable: >> >> [_A, _B, _Cs] = re:split(?b2l(AuthSession), ":", >> [{return, list}, {parts, 3}]), >> >> [_A, _B, _Cs] = re:split(?b2l(AuthSession), ":", >> [{return, list}, {parts, 3}] >> ), >> >> ----- >> >> LONG LIST WRAPPING: >> >> 4 for 8-space indent >> 3 for "aligned with nested structure in previous line" >> 5 for "single character indent" >> 9 for "indented to match correct nesting block" >> 3 for "4-space indent" >> 1 for "2 with indented case" >> >> Reminder: You could vote for multiple options for this question. >> >> Here is the code block formatted with single-character indent: >> >> case lists:member(revs, Options) of >> false -> >> []; >> true -> >> [{<<"revisions">>, {[{<<"start">>, Start}, >> {<<"ids">>, [revid_to_str(R) ||R ,_ RevIds]}]}}] >> end. >> >> And indented to match correct nesting block: >> >> case lists:member(revs, Options) of >> false -> >> []; >> true -> >> [ >> {<<"revisions">>, >> {[{<<"start">>, Start}, >> {<<"ids">>, [revid_to_str(R) ||R ,_ RevIds]} >> ]} >> } >> ] >> end. >> >> This was intended to be a question to which there really was no good >> answer. ;) As expected, results are across the board, except for >> "indented to match correct nesting block," which appears to be popular >> because it was probably the only layout one could glance at and have a >> hope of understanding. >> >> I don't think there is a good proposal to be made here. It is a judgment >> call, and I think any of "4-space indent," "8-space indent" or "indented >> to match correct nesting blocks" can be made to work. >> >> ----- >> >> LIST COMPREHENSION WRAP: >> >> 9 for "lined up for first term until || is reached >> 3 for "indented 4 spaces from {ok above" >> 2 for "everything indented 8 spaces" >> 1 for "4 spaces from expression start, e.g. after Docs" >> 1 for "Don't use multi-line list comprehensions! 4-space indent" >> 1 for "no idea" :D >> >> Code for "lined up for first term until || is reached": >> >> Docs = [Doc || {ok, Doc} <- [ >> couch_db:open_doc(Db2, DocInfo2, [deleted, conflicts]) >> || Docinfo2 <- DocInfos]], >> >> This was also a very ugly example that I found in our code that I wanted >> to use to highlight how difficult it can be to come up with a standard. >> The good news is that most people were in the 4- or 8-space camp, i.e. >> 1 or 2 level indents, and that perhaps the code needs refactoring. In >> the case of refactoring, I definitely agree with Bob: PRs with refactors >> should not be combined with PRs for whitespace, or at the very least >> should be 2 separate checkins within the same PR. >> >> There is no unique proposal for this other than to reference the initial >> proposal in this post: "Indent your code blocks with 4 spaces. Never use >> tabs or a mix of tabs and spaces. When additional indentation levels are >> needed, always increment by a multiple of 4 spaces." >> >> ----- >> >> VERTICAL SPACING: >> >> There was no poll question on this but it was brought up a few times on >> the list. Going from code and proposals, there are 2 options: >> >> 0 blank lines between function declarations differing only in guards >> 1 blank line between different function declarations, imports, etc. >> >> and >> >> 1 blank line between function declarations differing only in guards >> 2 blank lines between different function declarations, imports, etc. >> >> I can see arguments for both. By inspection most of our code follows >> the 0/1 approach, not the 1/2 approach favoured by Paul. >> >> -----
