added null coalesce operator to path

[kurtbrose]

No description provided.

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@0531ca2). Click here to learn what that means.
The diff coverage is 96.00%.

@@            Coverage Diff            @@
##             master     #143   +/-   ##
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  Coverage          ?   97.27%           
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  Files             ?       22           
  Lines             ?     2904           
  Branches          ?      415           
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  Hits              ?     2825           
  Misses            ?       50           
  Partials          ?       29           

Impacted Files	Coverage Δ
glom/core.py	97.40% <92.85%> (ø)
glom/test/test_path_and_t.py	99.21% <100.00%> (ø)
glom/chainmap_backport.py	69.87% <0.00%> (ø)
glom/__main__.py	33.33% <0.00%> (ø)
glom/test/test_basic.py	100.00% <0.00%> (ø)
glom/mutation.py	98.75% <0.00%> (ø)
glom/test/test_reduction.py	100.00% <0.00%> (ø)
glom/test/test_mutation.py	97.94% <0.00%> (ø)
glom/tutorial.py	100.00% <0.00%> (ø)
glom/test/test_streaming.py	100.00% <0.00%> (ø)
... and 14 more

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[mahmoud]

Stopping by to note that Python's PEP 505 on this got deferred. To me that's notable. Glom has an easy way of getting a default out of a long line of attribute accesses (glom(target, 'a.b.c.d', default=None)). And maybe once in my entire programming career have I ever needed to "get strict again" (i.e., give me a None if b isn't present, but raise an error if there's a b but no c). To me that feels like pattern matching lite (or microlite), and we already have Match coming in! So I think I want to defer this, and leave the Path simple whenever possible. Hope this deferral makes sense to any and all reading this. If we end up having a clear cut use case, you know I'll happily revive it.