Changed InterestMode enum implementation

freqtrade/enums/interestmode.py

@@ -1,30 +1,24 @@
 from enum import Enum, auto
 from decimal import Decimal
+from freqtrade.exceptions import OperationalException
 
 one = Decimal(1.0)
 four = Decimal(4.0)
 twenty_four = Decimal(24.0)
 
 
-class FunctionProxy:
-    """Allow to mask a function as an Object."""
+class InterestMode(Enum):
 
-    def __init__(self, function):
-        self.function = function
+    HOURSPERDAY = "HOURSPERDAY"
+    HOURSPER4 = "HOURSPER4"  # Hours per 4 hour segment
 
     def __call__(self, *args, **kwargs):
-        return self.function(*args, **kwargs)
 
+        borrowed, rate, hours = kwargs["borrowed"], kwargs["rate"], kwargs["hours"]
 
-class InterestMode(Enum):
-    """Equations to calculate interest"""
-
-    # Interest_rate is per day, minimum time of 1 hour
-    HOURSPERDAY = FunctionProxy(
-        lambda borrowed, rate, hours: borrowed * rate * max(hours, one)/twenty_four
-    )
-
-    # Interest_rate is per 4 hours, minimum time of 4 hours
-    HOURSPER4 = FunctionProxy(
-        lambda borrowed, rate, hours: borrowed * rate * (1 + max(0, (hours-four)/four))
-    )
+        if self.name == "HOURSPERDAY":
+            return borrowed * rate * max(hours, one)/twenty_four
+        elif self.name == "HOURSPER4":
+            return borrowed * rate * (1 + max(0, (hours-four)/four))
+        else:
+            raise OperationalException(f"Leverage not available on this exchange with freqtrade")