Recursively declaring variables - python

Question

Normally I would never want to do this, but in this case I feel as though there's no alternative. I'm building a program in pyqt that has many label widgets, and alot of which are the same with the exception of a couple places on the geometry.

I would like to automate declaring them instead of having to declare them line by line which is taking up a lot of lines. It also looks pretty ugly.

Is there a way to say create ten variables like var1, var2, var3, etc. without having to declare them line by line?

Right now my code looks like-

self.folderheader1 = QtGui.QLabel(self.folders)
self.folderheader2 = QtGui.QLabel(self.folders)
self.folderheader3 = QtGui.QLabel(self.folders)
self.folderheader4 = QtGui.QLabel(self.folders)
...

You can accomplish what you want with setattr, but are you sure you want to? Why not create a dict or list instead? — mgilson
– mgilson, Commented Dec 17, 2013 at 7:58

mgilson · Accepted Answer · 2013-12-17 07:59:45Z

8

You can do this with setattr, but I don't recommend it:

for i in range(1,5):
    setattr(self, 'folderheader%s' % i, QtGui.QLabel(self.folders))

Instead, might I suggest a list?

self.folderheaders = [QtGui.Qlabel(self.folders) for _ in range(1, 5)]

Now instead of self.folderheaders1 you have self.folderheaders[0] which isn't really that different...

answered Dec 17, 2013 at 7:59

mgilson

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1 Comment

Joshua Strot Over a year ago

Thank you for the answer. The setattr works beautifully. However, I tried out your list method, and it worked much better and is much cleaner! Thank you very much.

thefourtheye · Accepted Answer · 2013-12-17 07:59:38Z

1

You can use a dict like this

self.foldersdict = {}
for i in range(100):
    self.foldersdict[i] = QtGui.QLabel(self.folders)

You can later access them like this,

self.foldersdict[1]

answered Dec 17, 2013 at 7:59

thefourtheye

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1 Comment

LiMar Over a year ago

Dictionary with integer key? Sound like recipe for list. self.foldersdict = [ QtGui.QLabel(self.folders) for _ in xrange(100)]

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