Python right-hand value binding

Question

This might be an extremely noob python question however I'm curious.

Is it possible to make right-hand value binding (not sure about terminology) in python?

Here's some code:

>>> d = {'a':1 , 'b': 2 }
>>> d['a']
1
>>> temp = d['a']
>>> temp
1
>>> temp = 4
>>> temp
4
>>> d
{'a': 1, 'b': 2}

Can we use temp as a shortcut of d['a']? So when we do temp = 4, the last line to print {'a': 4, 'b': 2}?

Does any syntax to do it exist or the only way to update the d['a'] value is by d['a'] = 4?

However if `d['a']` was a mutable object (e.g. a `list`) you could alter it (e.g. `append` an object) via `temp`. — jonrsharpe, May 15 '14 at 18:15
@AlexThornton I'm talking about a mutable value; you're right that keys can't be mutable/hashable — jonrsharpe, May 15 '14 at 18:17
@arshajii I suppose what I meant was that there isn't really easy pointer handling like for example in C. — anon582847382, May 15 '14 at 18:17
Perhaps not a duplicate, but certainly related: [Python: How do I pass a variable by reference?](http://stackoverflow.com/q/986006/395760) — , May 15 '14 at 18:24
@delnan: I was just about to post the same thing. Dupe hammer time anyway? — Martijn Pieters, May 15 '14 at 18:25
@delnan: [this post](http://stackoverflow.com/questions/15085529/why-doesnt-an-attribute-value-in-a-dictionary-within-a-class-refer-to-the-same) was closed as a dupe of that canonical post, I feel justified in closing this as a dupe of at least that one. — Martijn Pieters, May 15 '14 at 18:32

score 0 · Accepted Answer · answered May 15 '14 at 18:21

0

There is no such feature in Python. You could create an object that represents a reference to the according map entry and that has methods to set the the map's value, but that is not specifically supported by Python syntax.

answered May 15 '14 at 18:21

Ulrich Eckhardt

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Python right-hand value binding

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