init

1 files changed, 22 insertions, 0 deletions

diff --git a/src/Operators.hs b/src/Operators.hs
new file mode 100644
index 0000000..e57f885
--- /dev/null
+++ b/src/Operators.hs
@@ -0,0 +1,22 @@
+module Operators (
+    primitives
+    ) where
+
+import           Parser
+
+primitives :: [(String, [Expr] -> Expr)]
+primitives =
+    [
+    ("+", arithmetic (+))
+    , ("-", arithmetic (-))
+    , ("*", arithmetic (*))
+    , ("/", arithmetic div)
+    ]
+
+arithmetic :: (Integer -> Integer -> Integer) -> [Expr] -> Expr
+arithmetic op args = IntLiteral $ foldl1 op $ map unwrapNum args
+
+unwrapNum :: Expr -> Integer
+unwrapNum (IntLiteral n) = n
+unwrapNum _              = undefined
+