[Python-ideas] Provide __main__ for datetime and time

Terry Reedy tjreedy at udel.edu
Fri Apr 1 15:55:38 EDT 2016

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On 4/1/2016 2:02 PM, Michel Desmoulin wrote:
> As with my previous email about __main__ for random, uuid and os, I wish
> to suggest a similar __main__ for datetime.

File __main__ is for packages.  I believe none of the modules you 
mention are packages, so I presume you mean adding within the module 
something like

def main(args): ...

if __name__ = '__main__':
     from sys import args

or the equivalent in C.

 > The target audience may not
> be the same, so I'm making it a difference proposal.
> E.G:
> python -m datetime now => print(str(datetime.datetime.now())
> python -m datetime utcnow => print(str(datetime.datetime.utcnow())
> python -m time epoch => print(time.time())
> python -m datetime now "%d/%m/%Y" =>
> print(str(datetime.datetime.now().strftime("%d/%m/%Y"))
> python -m datetime utcnow "%d/%m/%Y" =>
> print(str(datetime.datetime.utcnow().strftime("%d/%m/%Y"))

What is the particular motivation for this package?  Should we add a 
command line interface to math?  So that

python -m math func arg => print(func(arg))
I am wondering what is or should be the general policy on the subject. 
How easy is this for C-coded modules?

Terry Jan Reedy

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