python_bin_hex_display.py

"""
This makes the python interpreter to print integers as hexadecimal or binary

this is based in a stack overflow answer but i cant find the original source :c
"""

import sys, math

def nbits(a, pad=4):
    """
    Number of bits needed to represent a integer including the padding desired
    """
    n = math.ceil(math.log2(abs(a)+1))
    if n % pad:
        n += (pad - (n % pad)) 
    return n

def group_bits(n, rep='x', digits_per_group=4, sep="_"):
    """
    Creates a string representing a integer in bin or hex dividing the 
    digits in groups of the specified size and adding padding if needed
    """
    if rep.lower() == 'x': # hex
        bits_per_digit = 4
    else: # bin
        bits_per_digit = 1
    bits_per_group = digits_per_group * bits_per_digit
    num_bits = nbits(n, bits_per_group)
    d = '{:0{}{}}'.format(
            n & ((1<<num_bits)-1), # truncate negative numbers to a certain size
            int(num_bits/bits_per_digit), # amount of leading zeros
            rep
        )
    return sep.join(d[k:k+digits_per_group] for k in range(0, len(d), digits_per_group))

def _out(o, rep='X', group_size=4):
    if type(o).__name__ in ('int', 'long'):
        print('0' + rep.lower() + group_bits(o, rep, digits_per_group=group_size))
        __builtins__._ = o
    else:
        sys.__displayhook__(o)

def hexon(size=4):
    sys.displayhook = lambda x: _out(x, rep='X', group_size=size)

def hexoff():
    sys.displayhook=sys.__displayhook__

def binon(size=4):
    sys.displayhook = lambda x: _out(x, rep='b', group_size=size)

binoff = hexoff