Layout_Alignment.md

Horizontal alignment example layouts

Last updated for brittany version 0.8.0.1.

Brittany would layout the following bindings as displayed here. If you change only the layout of these bindings in some way (e.g. if you initially entered these without any alignment) and pass it through brittany, you would (again) get the below versions.

nested alignment for patterns

func (MyLongFoo abc def) = 1
func (Bar       a   d  ) = 2
func _                   = 3

go []                 ""     = True
go [WildCard        ] ""     = True
go (WildCard   :rest) (c:cs) = go rest (c : cs) || go (WildCard : rest) cs
go (Union globs:rest) cs     = any (\glob -> go (glob ++ rest) cs) globs
go []                 (_:_)  = False
go (_:_)              ""     = False

alignment of function args and monadcomp bindings

myBinding =
  [ [ [ LeguEosb r1 (n2 - r1) fxvoNz    ymuSreje v
      , LeguEosb n2 (f3 - n2) oyphEmedn ymuSreje v
      , LeguEosb f3 (i4 - f3) fxvoNz    ymuSreje v
      , LeguEosb i4 (v5 - i4) oieha     ymuSreje v
      , LeguEosb v5 (j6 - v5) fxvoNz    ymuSreje v
      ]
    | oyphEmedn <- sdliWmguje
    , oieha     <- ohzvIp
    ]
  | v5 < j6
  , sdliWmguje <- zedoaregeuKilb tua1
  , ohzvIp     <- zedoaregeuKilb (0 - loy2)
  ]

pattern matching

If same number of pattern args, there is sub-alignment. Types are not inspected in any way for this.

transPartDesc = \case
  PartLiteral  s      -> [s]
  PartVariable _      -> []
  PartOptional x      -> transPartDesc x
  PartAlts     alts   -> alts >>= transPartDesc
  PartSeq      []     -> []
  PartSeq      (x:_)  -> transPartDesc x
  PartDefault    _  x -> transPartDesc x
  PartSuggestion ss x -> ss ++ transPartDesc x
  PartRedirect   _  x -> transPartDesc x
  PartReorder xs      -> xs >>= transPartDesc
  PartMany    x       -> transPartDesc x
  PartWithHelp _h x   -> transPartDesc x

record syntax, field alignment

action = do
  startA <- transRelPos start
  s1     <- get
  modify $ \s2 -> s2 { _ts_sequencePos = Nothing
                     , _ts_curNote     = _ts_curNote s1
                     , _ts_curTrans    = _ts_curTrans s1
                     , _ts_curBar      = _ts_curBar s1
                     , _ts_curBase     = _ts_curBase s1
                     }

items that are not single-line break up alignment

action = do
  _       <- string "set"
  bindId  <- onlySpaces *> ((,) <$> getPosition <*> parserIdent)
  marg    <- onlySpaces *> optionMaybe (char '(' *> parserParamDef <* char ')')
  localId <-
    onlySpaces *> (optionMaybe $ string "in" *> onlySpaces *> parserIdent)
  _    <- onlySpaces *> string "="
  expr <- spaces *> parserExpr
  pure $ CompNotParseItemBind bindId marg expr localId

consequently these <- are not aligned at all:

action = do
  normVal :: Float <- expectParamE
    =<< expectDynamic (Text.pack "foldInNormalize")
  ResponseNode folderC folderN <- uncurry callBExpectS
    =<< getKalinAndParams (Text.pack "foldInFolder")
  ResponseNode foldeeC foldeeN <- uncurry callBExpectS
    =<< getKalinAndParams (Text.pack "foldInFoldee")
  pure $ calc normVal folderC folderN foldeeC foldeeN