fixed

commit 1ee2b4f9c8f96b29071d29ed19e34c786c3c7481
parent 085c244b34572417f3216a775e443cafbc20026d
Author: Jared Tobin <jared@jtobin.io>
Date:   Mon, 24 Nov 2025 20:02:12 +0400

lib: basic Eq instance for Wider

Diffstat:
M
lib/Data/Word/Wider.hs
 | 
11
+++++++++--
M
lib/Numeric/Montgomery/Secp256k1/Curve.hs
 | 
2
+-

2 files changed, 10 insertions(+), 3 deletions(-)
diff --git a/lib/Data/Word/Wider.hs b/lib/Data/Word/Wider.hs
@@ -32,13 +32,17 @@ wrapping_neg# w = plusWord# (not# w) 1##
 -- | Little-endian wider words.
 data Wider = Wider !(# Word#, Word#, Word#, Word# #)
 
+instance Eq Wider where
+  Wider a == Wider b = C.decide (C.ct_eq_wider# a b)
+
 instance Show Wider where
   show (Wider (# a, b, c, d #)) =
        "(" <> show (W# a) <> ", " <> show (W# b) <> ", "
     <> show (W# c) <> ", " <> show (W# d) <> ")"
 
 instance NFData Wider where
-  rnf (Wider a) = case a of (# _, _, _, _ #) -> ()
+  rnf (Wider a) = case a of
+    (# _, _, _, _ #) -> ()
 
 instance Num Wider where
   (+) = add
@@ -47,7 +51,10 @@ instance Num Wider where
   abs = id
   fromInteger = to
   negate = to . negate . from
-  signum = to . signum . from
+  signum a
+    | a == Wider (# 0##, 0##, 0##, 0## #) = 0
+    | otherwise = 1
+
 -- construction / conversion --------------------------------------------------
 
 -- | Construct a 'Wider' word from four 'Words', provided in
diff --git a/lib/Numeric/Montgomery/Secp256k1/Curve.hs b/lib/Numeric/Montgomery/Secp256k1/Curve.hs
@@ -39,7 +39,7 @@ instance Num Montgomery where
   a * b = mul a b
   negate a = neg a
   abs = id
-  signum = id
+  signum = id -- XX
   fromInteger = to . WW.to
 
 -- XX define constants here, current approach is fragile