MIT licensed by Li-yao Xia
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Used by 1 package in nightly-2021-04-06(full list with versions):

Show combinators Hackage Build Status

A minimal set of convenient combinators to write Show instances.

data MyType a
  = C a a                   -- a regular constructor
  | a :+: a                 -- an infix constructor
  | R { f1 :: a, f2 :: a }  -- a record

infixl 4 :+:

instance Show a => Show (MyType a) where
  showsPrec = flip precShows where
    precShows (C a b) = showCon "C" @| a @| b
    precShows (c :+: d) = showInfix ":+:" 4 c d
    precShows (R {f1 = e, f2 = f}) =
      showRecord "R" ("f1" .=. e &| "f2" .=. f)


  • Fix a bug where showRecord would not parenthesize the output if a high enough precedence were supplied.

  • Added showInfixl, showInfixr, showInfixl', showInfixr'.

Initial version