shithub: MicroHs

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Add readInteger

--- a/lib/Data/Integer.hs

+++ b/lib/Data/Integer.hs

@@ -4,6 +4,7 @@

   Integer,

   intToInteger,

   integerToInt,

+  readInteger,

   _integerToIntList,

   _intListToInteger,

   ) where

@@ -272,6 +273,9 @@

 twoI :: Integer

 twoI = I Plus [2]

+tenI :: Integer

+tenI = I Plus [10]

+

 negOneI :: Integer

 negOneI = I Minus [1]

@@ -287,6 +291,13 @@

 showInteger' xs = showInteger' (trim0 xs') ++ [chr (ord '0' + d)]

   where

     (xs', [d]) = quotRemD xs 10

+

+readInteger :: String -> Integer

+readInteger ('-':ds) = negate (readUnsignedInteger ds)

+readInteger ds       =         readUnsignedInteger ds

+

+readUnsignedInteger :: String -> Integer

+readUnsignedInteger = foldl (\ r c -> r * tenI + intToInteger (ord c - ord '0')) zeroI

 eqI :: Integer -> Integer -> Bool

 eqI (I sx xs) (I sy ys) = eqSign sx sy && eqList (==) xs ys

-- 

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