A simple class for filtering mappings

dict_filter.py

class dict_filter:
	def __init__(self, key=None, value=None, key_condition=None, value_condition=None):
		self.key = key
		self.value = value
		self.key_condition = key_condition
		self.value_condition = value_condition

	def __call__(self, source):
		K, V, KC, VC = self.key, self.value, self.key_condition, self.value_condition

		if KC and VC:
			if K and V:
				return {K(k): V(v) for k, v in source.items() if KC(k) and VC(v)}
			elif K:
				return {K(k): v for k, v in source.items() if KC(k) and VC(v)}
			elif V:
				return {k: V(v) for k, v in source.items() if KC(k) and VC(v)}
			else:
				return {k: v for k, v in source.items() if KC(k) and VC(v)}
		elif KC:
			if K and V:
				return {K(k): V(v) for k, v in source.items() if KC(k)}
			elif K:
				return {K(k): v for k, v in source.items() if KC(k)}
			elif V:
				return {k: V(v) for k, v in source.items() if KC(k)}
			else:
				return {k: v for k, v in source.items() if KC(k)}
		elif VC:
			if K and V:
				return {K(k): V(v) for k, v in source.items() if VC(v)}
			elif K:
				return {K(k): v for k, v in source.items() if VC(v)}
			elif V:
				return {k: V(v) for k, v in source.items() if VC(v)}
			else:
				return {k: v for k, v in source.items() if VC(v)}
		else:
			if K and V:
				return {K(k): V(v) for k, v in source.items()}
			elif K:
				return {K(k): v for k, v in source.items()}
			elif V:
				return {k: V(v) for k, v in source.items()}
			else:
				return dict(source)