What is the accepted python alternative to C++ overloaded input stream operators?

Question

In C++, you can do this to easily read data into a class:

istream& operator >> (istream& instream, SomeClass& someclass) {
    ...
}

In python, the only way I can find to read from the console is the "raw_input" function, which isn't very adaptable to this sort of thing. Is there a pythonic way to go about this?

Answer 1

You are essentially looking for deserialization. Python has a myriad of options for this depending on the library used. The default is python pickling. There are lots of other options you can have a look here.

Answer 2

Rather than use raw_input, you can read from sys.stdin (a file-like object):

import sys
input_line = sys.stdin.readline()
# do something with input_line

Answer 3

No, there's no widespread Pythonic convention for "read the next instance of class X from this open input text file". I believe this applies to most languages, including e.g. Java; C++ is kind of the outlier there (and many C++ shops forbid the operator>> use in their local style guides). Serialization (to/from JSON or XML if you need allegedly-human readable text files), suggested by another answer, is one possible approach, but not too hot (no standardized way to serialize completely general class instances to either XML or JSON).