show-combinators

Combinators to write Show instances

https://github.com/Lysxia/show-combinators#readme

Version on this page:0.1.0.0@rev:1
LTS Haskell 22.34:0.2.0.0@rev:2
Stackage Nightly 2024-09-10:0.2.0.0@rev:2
Latest on Hackage:0.2.0.0@rev:2

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MIT licensed by Li-yao Xia
Maintained by [email protected]
This version can be pinned in stack with:show-combinators-0.1.0.0@sha256:08d7c0c4eb06c8e3fc84ba3d79d748b0f265367f63a0a12855f984ab243aed27,1112

Module documentation for 0.1.0.0

Depends on 1 package(full list with versions):
base

Show combinators

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)