print: Tips and tricks

[snippsat]

carriage return \r and the backspace \b don't work within IDLE(don't use it all) because it uses a text control that doesn't render return/backspace properly.
Run it from command line eg python3 pro_bar.py,or use better REPL like ipython or ptpython.
Run it interactive -i from command should also work as then it will not us IDLE.

λ python -i pro_bar.py
Activity: [#########################] 100% Ready

# Using -i mean that can continue explorer code 
>>> i
99
>>> status_bar
<function status_bar at 0x03410858>

Eg with ptpython or ipython i can just copy all code straight into REPL and it work.
With IDLE can not copy in code at all,has to use Enter after each line.

λ ptpython
>>> import sys, time
...
... def status_bar(activity, progres):
...     length = 25
...     block = int(round(length*progres))
...     msg = "\r{0}: [{1}] {2}%".format(activity, "#"*block + "-"*(length-block), round(progres*100, 2))
...     if progres >= 1:
...         msg += " Ready\r\n"
...     sys.stdout.write(msg)
...     sys.stdout.flush()
...
...
...
... # usage
... for i in range(100):
...     time.sleep(0.1)
...     status_bar('Activity', i/100.0)
... status_bar('Activity', 1)
Activity: [#########################] 100% Ready