The Zen of python tells us: There should be one and only one obvious way to do it.
This is difficult to put in practice when it comes to the following situation.
A class receives a list of documents. The output is a dictionary per document with a variety of key/value pairs. Every pair depends on a previous calculated one or even from other value/pairs of other dictionary of the list.
This is a very simplified example of such a class.
What is the “obvious” way to go? Every method adds a value/pair to every of the dictionaries.
class T():
def __init__(self,mylist):
#build list of dicts
self.J = [{str(i):mylist[i]} for i in range(len(mylist))]
# enhancement 1: upper
self.method1()
# enhancement 2: lower
self.J = self.static2(self.J)
def method1(self):
newdict = []
for i,mydict in enumerate(self.J):
mydict['up'] = mydict[str(i)].upper()
newdict.append(mydict)
self.J = newdict
@staticmethod
def static2(alist):
J = []
for i,mydict in enumerate(alist):
mydict['down'] = mydict[str(i)].lower()
J.append(mydict)
return J
@property
def propmethod(self):
J = []
for i,mydict in enumerate(self.J):
mydict['prop'] = mydict[str(i)].title()
J.append(mydict)
return J
# more methods extrating info out of every doc in the list
# ...
self.method1() is simple run and a new key/value pair is added to every dict. The static method 2 can also be used. and also the property.
Out of the three ways I discharge @property because I am not adding another attribute. From the other two which one would you choose?
Remember the class will be composed by tens of this Methode that so not add attributes. Only Update (add keine pair values) dictionaries in a list.
I can not see the difference between method1 and static2.
thx.
