Decimal

src/adv_types.py

@@ -57,5 +57,30 @@ class f32: pass
 @pwp_number("<d", float)
 class f64: pass
 
-@pwp_number("<BiI", Decimal)
-class decimal: pass
+class decimal:
+    size = struct.calcsize("<qb")
+
+    def __init__(self, value):
+        self.value = Decimal(value)
+
+    def to_com(self):
+        sign, digits, exponent = self.value.as_tuple()
+
+        if not isinstance(exponent, int):
+            raise ValueError("Cannot serialize NaN or Infinity")
+
+        scale = -exponent
+        integer = int("".join(map(str, digits)))
+
+        if sign:
+            integer = -integer
+
+        return struct.pack("<qb", integer, scale)
+
+    @classmethod
+    def from_com(cls, data, offset=0):
+        integer, scale = struct.unpack_from("<qb", data, offset)
+
+        value = Decimal(integer) / (Decimal(10) ** scale)
+
+        return cls(value), offset + cls.size