Avoid overwriting Python functions

[sbellem]

From @sbellem on August 17, 2017 23:17

For example the function hash() in reliablebroadcast.py could be confused with the Python built-in function hash(). It could perhaps be renamed something like sha256_digest() just to avoid confusion and potential problems in the future.

Another example is the usage of the callable namedinput() (e.g. in reliablebroadcast():

def reliablebroadcast(sid, pid, N, f, leader, input, receive, send):
    """Reliable broadcast ... """"
    # ...
    if pid == leader:
        # The leader erasure encodes the input, sending one strip to each participant
        m = input()  # block until an input is received
    # ...

input() is also a Python built-in function. If somehow input() is the best name, one trick that is often recommended is to suffix the name with an underscore _. In this case the callable would be renamed input_() and the above code snippet would become:

def reliablebroadcast(sid, pid, N, f, leader, input, receive, send):
    """Reliable broadcast ... """"
    # ...
    if pid == leader:
        # The leader erasure encodes the input, sending one strip to each participant
        m = input_()  # block until an input is received
    # ...

Notice how the highlighting of the input() function differs in each code snippet. I assume that is because Github uses MagicPython to highlight the code and MagicPython highlights Python built-in functions.

See related thread https://www.reddit.com/r/pythontips/comments/4m9wiw/avoid_overwriting_python_functions/?st=j6h17gu8&sh=f483ed6e

Also somewhat related Function and method arguments in PEP 8:

If a function argument's name clashes with a reserved keyword, it is generally better to append a single trailing underscore rather than use an abbreviation or spelling corruption. Thus class_ is better than clss. (Perhaps better is to avoid such clashes by using a synonym.)

Copied from original issue: amiller/HoneyBadgerBFT#23