This post is a follow-up to the post I made over the weekend.

Just in case anyone is interested, I thought I’d add a few examples of how set operations would be used with Google+, as well as a few ideas for how they could be implemented in the bar that you already type circles/people in to. As reference, I have a couple of fictional circles described below:

Friends | Work | Family | Video Game Friends |

Jimmy | Franklin | Arnold | Gabe |

Kenny | Gabe | Bob | Markus |

Lenny | Heather | Cindi | Romero |

Manny | Jimmy | Drew | Will |

Neddy | | Enrique | Enrique |

Patti | | Franklin | Arnold |

| | | Franklin |

Let’s say I want to post a message to my co-workers and my family. G+ makes this easy

In set notation, this looks like

Work ∪ Family = {Franklin, George, Heather, Jimmy, Arnold, Bob,
Cindi, Drew, Enrique}

It doesn’t matter that Franklin is in both circles. He’ll just get the post once. But what if I wanted to make a post visible to all of my co-workers *except* those who are also family members? In this case there is only one, but what if I couldn’t remember, or it were more complicated than that? Set operations could make quick work of this one, it is denoted by the intuitive:

Work - Family = {Franklin, George, Heather}

Those family members who are not in Work are irrelevant to the whole operation, and were never under consideration for the post.

Now it could get a little more complicated. What if I want to post something visible to people who are both video gamers *and* family members. Currently G+ does not allow this *intersection *operator, that would look something like this:

Video Game Friends ∩ Family = {Enrique, Arnold}

The resulting set for my family would actually be smaller than the one in my example, but you get the point.

The final bit of coolness would be the symmetric difference. It is probably the least practical, but I’d love to see it implemented for completeness’ sake. What if I wanted to post to people who were either Friends or co-workers, but *not* both. This seems unlikely, but it’s possible. It would look like this:

Friends Δ Work = {Kenny, Lenny, Manny, Neddy, Patti, Franklin,
George, Heather}

Notably absent is Jimmy, but he probably gets enough of me at work and as friends anyway…

So, if G+ adopted these set operations, they wouldn’t have to be hard to use. In fact, you wouldn’t even need to use those goofy set symbols, instead, might I suggest the following:

Set Operation | G+ symbol |

∪ (Union) | +
, (commas, like a list) |

- (Complement) | - |

∩ (Intersection) | & |

Δ (symetric difference)
Probably not even needed... | % (if anyone really wanted it) |

I’d welcome any other comments or suggestions if you’ve got any better/other ideas.

As a bonus, try and figure out who would get this post if I shared it using the following expression:

((Video Game Friends + Friends) - (Work - Family))