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CCSDSPy / ccsdspy

I/O interface and utilities for CCSDS binary spacecraft data in Python. Library used in flight missions at NASA, NOAA, and SWRI
https://ccsdspy.org
BSD 3-Clause "New" or "Revised" License
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Make the load method of FixedLength and VariableLength return the file stream argument at the location where it was before the call #111

Closed tloubrieu-jpl closed 7 months ago

tloubrieu-jpl commented 7 months ago

That would be easy to implement in the _load function.

It is needed when the same stream is parsed multiple times, in my case, for 1. decision_packet (when different packets definitions can be used with the same APID), 2. calculate a CRC (see discussion https://github.com/CCSDSPy/ccsdspy/discussions/108#discussioncomment-8425180)

That could be optional with an argument 'return_file_where_it_was' default to False to make the code backward compatible ?

Let me know, your thoughts on that.

ddasilva commented 7 months ago

Can you try this? This is the Pythonic way to do it, I believe.

pos = file.tell()
results = pkt.load(fh)
file.seek(pos)

I haven't seen any other APIs support the type of option you're proposing.. and it should be pretty easy without it so I'm hesitant to add a new keyword argument right now.

tloubrieu-jpl commented 7 months ago

Ok, I understand your point. In my code I am parsing 3 times the same stream which made it easier to have that feature in ccsdspy, but I can as well encapsulate the lines you gave in a function to make my code lighter. That will work for me. Thanks @ddasilva

ddasilva commented 7 months ago

Np. It's not a huge deal either way, if it's useful for you to have it this way then I'll accept a pull request. Just call it load(..., reset_file_obj=False) and make sure it has proper doc + tests.