For the last month, I’ve been reading and rereading these two and putting them together in a staged reading. Impossible of course now but not once. Nora and Joan appear to have been at least acquaintances; Ephron included a recipe by Didion in her self-published cookbook. Or I imagine two scenes in a movie, one getting “off a DC-7 at the old Idlewild temporary airport” in the 50’s [Didion], the other “packing up a rental car on graduation day and setting off to New York” in the 60’s.
Continuing this idea in a Boolean way,

Ephron, not Didion
Ephron liked jello molds
Ephron was funny.

Didion not Ephron
Didion doesn’t always fuss about how she looks.

Ephron and Didion
Both were bicoastal
Both were journalists in a time when women were discriminated against/dismissed
Both were cynical about politics
Both had husbands that they were deeply in love with.

Ephron or Didion
Ephron: “i’d known since I was a child that I was going to live in New York and that everything in between would be just an intermission. I thought it was going to be the most exciting, magical, fraught with possibility place that you could ever live… And I’d turned out to be right.” [from Journalism: A Love Story]
Didion: “All I knew is that it was very bad when I was twenty-eight. Everything that was said to me I seemed to have heard before, and I could no longer listen. … There were certain parts of the City which I had to avoid.” [from Good bye To All That]

If you couldn’t be Ephron and Didion, would you be Ephron or Didion.