So, is there a method to define self referencing dictionary of lambda functions which can be used to call different methods based upon the keys? Consider a small example of what is intended?
class A:
d = {
"add": lambda p1, p2: self.add(p1, p2),
"minus": lambda p1, p2: self.minus(p1, p2),
"multiply": lambda p1, p2: self.multiply(p1, p2),
"divide": lambda p1, p2: self.divide(p1, p2)
}
def add(self, p1, p2):
return p1+p2
def minus(self, p1, p2):
return p1-p2
def multiply(self, p1, p2):
return p1*p2
def divide(self, p1, p2):
return p1/p2
If I try the following:
a = A()
a.d["add"](1,2)
The above line throws an error:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "<stdin>", line 3, in <lambda>
NameError: name 'self' is not defined
What can be the best method to handle this?
In this case, your add, minus, etc. methods can be static, hence not require the instance of A, so your lambdas would be "add": lambda p1, p2: A.add(p1, p2), etc:
class A:
d = {
"add": lambda p1, p2: A.add(p1, p2),
"minus": lambda p1, p2: A.minus(p1, p2),
"multiply": lambda p1, p2: A.multiply(p1, p2),
"divide": lambda p1, p2: A.divide(p1, p2)
}
@staticmethod
def add(p1, p2):
return p1+p2
@staticmethod
def minus(p1, p2):
return p1-p2
@staticmethod
def multiply(p1, p2):
return p1*p2
@staticmethod
def divide(p1, p2):
return p1/p2
As your d dictionary is static (class field) you can't call the instance methods. You could if you initialized it in the __init__ of A:
class A:
def __init__(self):
self.d = {
"add": lambda p1, p2: self.add(p1, p2),
"minus": lambda p1, p2: self.minus(p1, p2),
"multiply": lambda p1, p2: self.multiply(p1, p2),
"divide": lambda p1, p2: self.divide(p1, p2)
}
def add(self, p1, p2):
return p1+p2
def minus(self, p1, p2):
return p1-p2
def multiply(self, p1, p2):
return p1*p2
def divide(self, p1, p2):
return p1/p2
In both cases
a = A()
a.d["add"](1,2)
would work.