hascal 1.1 → 1.3

raw patch · 3 files changed

+130/−47 lines, 3 filesnew-uploaderPVP ok

version bump matches the API change (PVP)

API changes (from Hackage documentation)

Files

• Hascal.hs +99/−22
• Main.hs +6/−5
• hascal.cabal +25/−20

@@ -1,67 +1,144 @@--- |'Hascal' is both a simple but extendable calculator library for Haskell+-- |Hascal is both a simple but extendable calculator library for Haskell -- and a command-line program using it. --  -- Also, its source code is a nice example for a minimalistic Haskell project.+-- +-- Some examples for the usage of the command-line program:+-- +-- >>> hascal 1+2+-- 3.0+-- +-- >>> hascal 1+2*3-4/198^2+-- 6.99989796959493929190898887868584838281807978777676+-- +-- Also, preceding exclamation marks mean that the following number is+-- imaginary, that is, you have to multiply it with i. E.g.:+-- +-- >>> hascal _1 ^ 0.5+-- !1.0+-- +-- And as you can see, negative numbers are preceded by a underscore.+-- +-- Although hascal itself doesn't understand brackets, you can use your shell+-- to get that functionality, like this (using bash):+-- +-- >>> hascal e ^ $(hascal i*pi)+-- -1.0+-- +-- Speaking of shells, you should consider that your shell might extend an+-- asterisk (*) to the files at the current directory, like here:+-- +-- >>> echo *+-- _darcs dist hascal.cabal Hascal.hs LICENSE Main.hs README.org Setup.hs+-- +-- That's why this might not work:+-- +-- >>> hascal 1 * 2+-- Error. :(+-- +-- But you could do this instead:+-- +-- >>> hascal 1*2+-- 2+-- +-- Yeah, that's it. Hascal is really minimalistic.+-- And I'm not planning to extend it much. module Hascal (+  -- * Types+  -- |Just re-exporting the 'Complex' data-type for simplicity and comfort.+  Complex,   -- * Functions   -- ** Operators   operators,   -- ** Evaluators   eval,-  hascal+  hascal,+  -- ** Pretty Printers+  prettyPrint   ) where -import           Control.Arrow     (second)-import           Data.Function     (on)-import           Data.Number.CReal +import Control.Arrow (second)+import Data.Complex  (Complex(..))+import Data.Functor  ((<$>))+import Data.List     (find) ++ -- |'operators' is the default list of operators. --  -- An operator consists of one character and a function with of type--- @CReal -> CReal -> CReal@.+-- @Number -> Number -> Number@. --  -- 'operators' includes: -- --- * addition, represented by @\'+\'@+-- * addition, represented by @\'+\'@, -- --- * subtraction, represented by @\'-\'@+-- * subtraction, represented by @\'-\'@, -- --- * multiplication, represented by @\'c\'@+-- * multiplication, represented by @\'c\'@, -- --- * division, represented by @\'\/\'@+-- * division, represented by @\'\/\'@, -- --- * exponentiation, represented by @\'^\'@+-- * exponentiation, represented by @\'^\'@, and -- --- * logarithming (with flipped arguments, see below), represented by @\'?\'@+-- * logarithming (with flipped arguments, see below), represented by @\'?\'@, --  -- such that these laws are held: --  -- > (a - b == c) == (a == b + c) -- > (a / b == c) == (a == b * c) -- > (a ? b == c) == (a == b ^ c)-operators :: [(Char, CReal -> CReal -> CReal)]+operators :: RealFloat t+          => [(Char, Complex t -> Complex t -> Complex t)] operators = [ ('+', (+))             , ('-', (-))             , ('/', (/))             , ('*', (*))             , ('^', (**))             , ('?', flip logBase)-            ]-- Respecting operator precedence,-             -- you can add custom infix operators.+            ] + -- |'eval' gets a list of operators and a string containing a mathematical -- expression/term which only uses those operators listed in the first -- argument, and returns the result of that term.-eval :: [(Char, CReal -> CReal -> CReal)] -> String -> CReal-eval []          a = read a-eval l@((c,f):s) a | z /= ""   = on f (eval l.($m)) fst snd-                   | otherwise = eval s a-                   where m@(_,z) = second (drop 1) $ break (==c) a+eval :: (Read t, RealFloat t)+     => [(Char, Complex t -> Complex t -> Complex t)]  -- ^ list of operators+     -> String                                         -- ^ string containing term+     -> Maybe (Complex t)                              -- ^ just result, or nothing+eval []          ('!':a) = ((0:+1)*) <$> findOrRead a+eval []          ('_':a) = negate <$> findOrRead a+eval []          a       = findOrRead a+eval l@((c,f):s) a       | z /= ""   = case (eval l y,eval l z) of+                                         (Just n,Just m) -> Just (f n m)+                                         _               -> Nothing+                         | otherwise = eval s a+                         where (y,z) = second (drop 1) $ break (==c) a  +findOrRead :: (Read t, Floating t) => String -> Maybe (Complex t)+findOrRead s = maybe (maybeRead s) (Just . fst) $+               find ((==s) . snd) [(pi:+0,"pi"),(exp 1:+0,"e"),(0:+1,"i")]+++maybeRead :: (Read t, Num t) => String -> Maybe (Complex t)+maybeRead s | any (null . snd) (reads s :: [(Double,String)])+            = Just (read s:+0)+            | otherwise+            = Nothing++ -- |'hascal' is the default evaluator: -- --- > hascal = eval operators-hascal :: String -> CReal+-- @ hascal = 'eval' 'operators' @+hascal :: (Read t, RealFloat t) => String -> Maybe (Complex t) hascal = eval operators+++-- |'prettyPrint' prints a number nicely.+-- E.g., it doesn't show the real or imaginary part of the number if it's @0@.+prettyPrint :: (Show t, RealFloat t) => Complex t -> String+prettyPrint (r:+0) = show r+prettyPrint (0:+i) = '!' : show i+prettyPrint (r:+i) = show r ++ " + !" ++ show i

@@ -1,11 +1,12 @@ module Main where -import           Control.Monad      (liftM2, unless)-import           Data.Number.CReal-import           Hascal-import           System.Environment (getArgs)+import Control.Monad+import Hascal+import System.Environment+import Data.Number.CReal   main :: IO () main = getArgs >>= liftM2 unless null-                   (putStrLn . showCReal 80 . hascal . concat)+       (putStrLn . maybe "Error. :(" prettyPrint .+        (hascal :: String -> Maybe (Complex CReal)) . concat)

@@ -1,26 +1,30 @@-name:                hascal-version:             1.1-synopsis:            a minimal, extensible and precise calculator-description:         Hascal is a minimal calculator with infix-operations-                     supporting addition, subtraction, division, multiplication,-		     exponentiation and logarithming. Brackets are not supported-		     yet.-		     Futhermore, it's easy to add custom operators.-stability:           provisional-category:            Math, Console, Tools, Utility, Utils, Parsing-homepage:            https://github.com/MekeorMelire/hascal-bug-reports:         https://github.com/MekeorMelire/hascal/issues-license:             GPL-license-file:        LICENSE-copyright:           © 2012 Mekeor Melire-author:              Mekeor Melire-maintainer:          Mekeor Melire <mekeor.melire@googlemail.com>-tested-with:         GHC ==7.0.4-cabal-version:       >= 1.6-build-type:          Simple+name:          hascal+version:       1.3+synopsis:      A minimal, extensible and precise calculator+description:   Hascal is a minimal calculator with infix-operations+               supporting addition, subtraction, division, multiplication,+               exponentiation and logarithming.+               Futhermore, it's easy to add custom operators.+stability:     provisional+category:      Math, Console, Tools, Utility, Utils, Parsing+homepage:      http://darcsden.com/mekeor/hascal+bug-reports:   https://github.com/MekeorMelire/hascal/issues+license:       GPL+license-file:  LICENSE+copyright:     2012 Mekeor Melire+author:        Mekeor Melire <mekeor.melire@googlemail.com>+maintainer:    Mekeor Melire <mekeor.melire@googlemail.com>+tested-with:   GHC ==7.0.4+cabal-version: >= 1.6+build-type:    Simple   source-repository head+  type:     darcs+  location: http://darcsden.com/mekeor/hascal+++source-repository head   type:     git   location: git://github.com/MekeorMelire/hascal.git @@ -29,6 +33,7 @@   build-depends:   base >2 && <5, numbers >= 3000   exposed-modules: Hascal   ghc-options:     -Wall+  executable hascal   build-depends:   base >2 && <5, numbers >= 3000