show-combinators 0.1.0.0 → 0.1.1.0

raw patch · 5 files changed

+133/−17 lines, 5 filesdep ~basePVP ok

version bump matches the API change (PVP)

Dependency ranges changed: base

API changes (from Hackage documentation)

Files

• CHANGELOG.md +7/−0
• README.md +1/−1
• show-combinators.cabal +5/−3
• src/Text/Show/Combinators.hs +99/−9
• test/test.hs +21/−4

@@ -0,0 +1,7 @@+# 0.1.1.0++- Added `showInfixl`, `showInfixr`, `showInfixl'`, `showInfixr'`.++# 0.1.0.0++Initial version

@@ -1,4 +1,4 @@-# Show combinators+# Show combinators [![Hackage](https://img.shields.io/hackage/v/show-combinators.svg)](https://hackage.haskell.org/package/show-combinators) [![Build Status](https://travis-ci.org/Lysxia/show-combinators.svg)](https://travis-ci.org/Lysxia/show-combinators)  A minimal set of convenient combinators to write `Show` instances. 

@@ -1,5 +1,5 @@ name:                show-combinators-version:             0.1.0.0+version:             0.1.1.0 synopsis:            Combinators to write Show instances description:   A minimal pretty-printing library for Show instances in Haskell.@@ -11,15 +11,17 @@ copyright:           2018 Li-yao Xia category:            Text build-type:          Simple-extra-source-files:  README.md+extra-source-files:  README.md, CHANGELOG.md cabal-version:       >=1.10+tested-with:         GHC == 7.10.3, GHC == 8.0.2, GHC == 8.2.2, GHC == 8.6.3  library   hs-source-dirs:      src   exposed-modules:     Text.Show.Combinators   build-depends:-    base >= 4.9 && < 5+    -- This upper bound is conservative+    base >= 4.8 && < 4.13   ghc-options:         -Wall   default-language:    Haskell2010 

@@ -1,6 +1,4 @@--- | Combinators for 'Show'------ The combinators below can be used to write 'Show' instances.+-- | Combinators to write 'Show' instances. -- -- The following type illustrates the common use cases. --@@ -14,20 +12,33 @@ -- -- 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 (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)+--       'showRecord' \"R\" (\"f1\" '.=.' e '&|' \"f2\" '.=.' f) -- @  module Text.Show.Combinators   ( module Text.Show   , PrecShowS++    -- * Simple constructors and applications   , showCon   , showApp   , (@|)++    -- * Infix constructors   , showInfix   , showInfix'++    -- ** Combinators for associative operators+    -- | Use with care, see 'showInfixl'.+  , showInfixl+  , showInfixl'+  , showInfixr+  , showInfixr'++    -- * Records   , ShowFields   , showRecord   , showField@@ -46,6 +57,23 @@ type PrecShowS = Int -> ShowS  -- | Show a constructor.+--+-- Possible constructor names are:+--+-- - regular constructors (e.g., @\"Left\"@);+-- - parenthesized infix constructors (e.g., @\"(:)\"@);+-- - smart constructors, for abstract types (e.g., @\"Map.fromList\"@).+--+-- === __Example with smart constructor__+--+-- @+-- instance (Show k, Show v) => Show (Map k v) where+--   showsPrec = 'flip' precShows where+--     precShows m = 'showCon' \"Map.fromList\" '@|' Map.toList m+--+-- -- Example output:+-- -- > Map.fromList [(33, True), (55, False)]+-- @ showCon :: String -> PrecShowS showCon con _ = showString con @@ -67,8 +95,7 @@  -- | Show an applied infix operator with a given precedence. showInfix :: String -> Int -> PrecShowS -> PrecShowS -> PrecShowS-showInfix op prec showX showY d = showParen (d > prec)-  (showX (prec + 1) . showSpace . showString op . showSpace . showY (prec + 1))+showInfix op prec = showInfix_ op prec (prec + 1) (prec + 1)  -- | Show an applied infix operator with a given precedence. --@@ -80,6 +107,69 @@ showInfix' :: (Show a, Show b) => String -> Int -> a -> b -> PrecShowS showInfix' op prec x y = showInfix op prec (flip showsPrec x) (flip showsPrec y) +-- | Show an applied infix operator which is left associative (@infixl@).+-- Use with care.+--+-- This combinator assumes that, if there is another infix operator to the+-- left, it is either left associative with the same precedence, or it has a+-- different precedence.+-- An expression containing two operators at the same level with different+-- associativities is ambiguous.+--+-- By default, prefer 'showInfix' and 'showInfix''.+showInfixl :: String -> Int -> PrecShowS -> PrecShowS -> PrecShowS+showInfixl op prec = showInfix_ op prec prec (prec + 1)++-- | Show an applied infix operator which is left associative (@infixl@).+-- Use with care, see 'showInfixl'.+--+-- This is a shorthand for 'showInfixl' when the arguments types are instances+-- of 'Show'.+--+-- By default, prefer 'showInfix' and 'showInfix''.+showInfixl' :: (Show a, Show b) => String -> Int -> a -> b -> PrecShowS+showInfixl' op prec x y = showInfixl op prec (flip showsPrec x) (flip showsPrec y)++-- | Show an applied infix operator which is right associative (@infixr@).+-- Use with care.+--+-- This combinator assumes that, if there is another infix operator to the+-- right, it is either right associative with the same precedence, or it has a+-- different precedence.+-- An expression containing two operators at the same level with different+-- associativities is ambiguous.+--+-- By default, prefer 'showInfix' and 'showInfix''.+--+-- === __Example usage__+--+-- @+-- showList :: Show a => [a] -> PrecShowS+-- showList [] = showCon "[]"+-- showList (x : xs) = showInfixr ":" 5 (flip showsPrec x) (showList xs)+--+-- -- Example output:+-- -- > 0 : 1 : 2 : 3 : []+-- @+showInfixr :: String -> Int -> PrecShowS -> PrecShowS -> PrecShowS+showInfixr op prec = showInfix_ op prec (prec + 1) prec++-- | Show an applied infix operator which is right associative (@infixr@).+-- Use with care, see 'showInfixr'.+--+-- This is a shorthand for 'showInfixr' when the arguments types are instances+-- of 'Show'.+--+-- By default, prefer 'showInfix' and 'showInfix''.+showInfixr' :: (Show a, Show b) => String -> Int -> a -> b -> PrecShowS+showInfixr' op prec x y = showInfixr op prec (flip showsPrec x) (flip showsPrec y)++-- | An internal combinator for infix operators, to explicitly update the+-- precedence levels on each side.+showInfix_ :: String -> Int -> Int -> Int -> PrecShowS -> PrecShowS -> PrecShowS+showInfix_ op prec precX precY showX showY d = showParen (d > prec)+  (showX precX . showSpace . showString op . showSpace . showY precY)+ -- | Strings representing a set of record fields separated by commas. -- They can be constructed using ('.=.') and ('@|'), or using 'showField' and -- 'appendFields'.@@ -103,7 +193,7 @@ -- This is an infix shorthand for 'showField' when the value type is an -- instance of 'Show'. ----- > field .=. x = showField field (flip showsPrec x)+-- > field .=. x   =   showField field (flip showsPrec x) (.=.) :: Show a => String -> a -> ShowFields field .=. x = showField field (flip showsPrec x) 

@@ -21,22 +21,39 @@ _showsMyType' (R {f1 = e, f2 = f}) =   showRecord "R" ("f1" .=. e &| "f2" .=. f) +showL :: [Int] -> PrecShowS+showL [] = showCon "[]"+showL (x : xs) = showInfixr ":" 5 (flip showsPrec x) (showL xs)++-- snoc lists+showR :: [Int] -> PrecShowS+showR [] = showCon "[]"+showR (x : xs) = showInfixl ":" 5 (showR xs) (flip showsPrec x)+ check :: Show a => (a -> PrecShowS) -> a -> IO ()-check show' x =+check show' x = assertEqual s s'+  where+    s = show x+    s' = show' x 0 ""++assertEqual :: (Eq a, Show a) => a -> a -> IO ()+assertEqual s s' =   if s == s' then     return ()   else     fail $ show (s, s')-  where-    s = show x-    s' = show' x 0 "" +unPS :: (a -> PrecShowS) -> a -> String+unPS p x = p x 0 ""+ main :: IO () main = do   check smt1 (C () ())   check smt2 (C (C () ()) (() :+: ()))   check smt2 ((() :+: ()) :+: (() :+: ()))   check smt2 (R (C () ()) (C () ()))+  assertEqual (unPS showL [1,2,3]) "1 : 2 : 3 : []"+  assertEqual (unPS showR [1,2,3]) "[] : 3 : 2 : 1"   where     smt1 = showsMyType (flip showsPrec)     smt2 = showsMyType smt1