Expose `task.in_stream.channels_to_read = "temp0:4"` as `task.in_stream["temp0:4"]`

[epage]

In discussing another NI API, the idea of indexing calls besides configuration came up. I then was considering where it'd even make sense within DAQmx. Reading is one case.

[epage]

The downside is that the python API is built on top of the C API.

Option 1 for implementing this:

def read(self, ...):
    if self._channels_to_read:
        backup = task.in_stream.channels_to_read
        task.in_stream.channels_to_read = self._channels_to_read
        try:
            ... read ...
        except:
            task.in_stream.channels_to_read = backup 
            raise
    else:
        ... read ...

This isn't very thread safe but I don't know if the python API has been focusing on thread safety or not.

Option 2 for implementing this

# In one of the Readers
def __init__(self, ...):
        task.in_stream.channels_to_read = channels_to_read

• This doesn't have a good auto-restore once done with the Reader
• This doesn't allow interleaved Readers (should we?)