Merge pull request #2 from Proclivis/master

Add logic functions.

Author: sharkdp

docs/Data/BigInt.md

@@ -78,6 +78,54 @@ prime :: BigInt -> Boolean
 
 Returns `true` if the number is prime, `false` otherwise.
 
+#### `not`
+
+``` purescript
+not :: BigInt -> BigInt
+```
+
+Returns a bit inverted number.
+
+#### `or`
+
+``` purescript
+or :: BigInt -> BigInt -> BigInt
+```
+
+Returns a bit or'ed number.
+
+#### `xor`
+
+``` purescript
+xor :: BigInt -> BigInt -> BigInt
+```
+
+Returns a bit xor'ed numnber.
+
+#### `and`
+
+``` purescript
+and :: BigInt -> BigInt -> BigInt
+```
+
+Returns a bit and'ed number.
+
+#### `shl`
+
+``` purescript
+shl :: BigInt -> Number -> BigInt
+```
+
+Shift the first number to the right by the second number of bits and return the result. Shifts in ones if the first number is negative.
+
+#### `shr`
+
+``` purescript
+shr :: BigInt -> Number -> BigInt
+```
+
+Shift the first number to the left by the second number of bits and return the result.
+
 #### `fromString`
 
 ``` purescript

src/Data/BigInt.js

@@ -90,3 +90,38 @@ exports.pow = function(x) {
     return x.pow(y);
   };
 };
+
+exports.not = function(x) {
+  return x.not();
+  };
+
+exports.or = function(x) {
+  return function(y) {
+    return x.or(y);
+  };
+};
+
+exports.xor = function(x) {
+  return function(y) {
+    return x.xor(y);
+  };
+};
+
+exports.and = function(x) {
+  return function(y) {
+    return x.and(y);
+  };
+};
+
+exports.shl = function(x) {
+  return function(n) {
+    return x.shiftLeft(n);
+  };
+};
+
+exports.shr = function(x) {
+  return function(n) {
+    return x.shiftRight(n);
+  };
+};
+

src/Data/BigInt.purs

@@ -10,6 +10,12 @@ module Data.BigInt
   , odd
   , prime
   , pow
+  , not
+  , or
+  , xor
+  , and
+  , shl
+  , shr
   , toNumber
   ) where
 
@@ -50,6 +56,24 @@ foreign import odd :: BigInt -> Boolean
 -- | Returns `true` if the number is prime, `false` otherwise.
 foreign import prime :: BigInt -> Boolean
 
+-- | Invert the bits.
+foreign import not :: BigInt -> BigInt
+
+-- | or the bits.
+foreign import or :: BigInt -> BigInt -> BigInt
+
+-- | Exlusive or the bits.
+foreign import xor :: BigInt -> BigInt -> BigInt
+
+-- | and the bits.
+foreign import and :: BigInt -> BigInt -> BigInt
+
+-- | shift the bits left and zero fill.
+foreign import shl :: BigInt -> Number -> BigInt
+
+-- | Shift the bits right and maintain pos/neg.
+foreign import shr :: BigInt -> Number -> BigInt
+
 -- | Parse a string into a `BigInt`, assuming a decimal representation. Returns
 -- | `Nothing` if the parse fails.
 -- |

test/Main.purs

@@ -5,7 +5,7 @@ import Control.Monad.Eff (Eff)
 import Control.Monad.Eff.Console (CONSOLE, log)
 import Data.Array (filter, range)
 import Data.BigInt (BigInt, abs, fromInt, prime, pow, odd, even, fromString,
-                    toNumber, fromBase, toString)
+                    toNumber, fromBase, toString, not, or, xor, and, shl, shr)
 import Data.Foldable (fold)
 import Data.Maybe (Maybe(..), fromMaybe)
 import Data.NonEmpty ((:|))
@@ -106,3 +106,13 @@ main = do
 
   log "Absolute value"
   quickCheck $ \(TestBigInt x) -> abs x == if x > zero then x else (-x)
+
+  log "Logic"
+  assert $ (not <<< not) one == one
+  assert $ or one three == three
+  assert $ xor one three == two
+  assert $ and one three == one
+
+  log "Shifting"
+  assert $ shl two one == four
+  assert $ shr two one == one