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Re: [p2-dev] Match/Context naming

On 02/23/2010 09:56 PM, Ian Bull wrote:
I'm not a big fan of Each vs. All as it sounds like Each doesn't include all the results.

The names give a hint on what the expression is applied to. When you author the query, you must consider if the expression is applied to 'each row' or to 'all rows'. The words Each and All are correlated, like Min/Max, Single/Multiple, etc.

I'm not saying that Each and All are the best terms. I'm just pointing out why I think they have some validity.

Here is some background (why Jeff and I arrived at these names).

MatchQueries are queries in which you can answer an elements inclusion by looking at the element alone. For example, is my name "Ian Bull". I doesn't matter who else is in the room. Context queries, on the other hand, require knowledge of all the other elements. Am I the tallest person in the room? This obviously depends on who else is in the room.

You still fit the description of being the tallest person. I.e. you "match" that description.

We broke the queries down this way because MatchQueries can be easily done in parallel. While you might be able to do ContextQueries in parallel, there is not general way.

That sounds like an evaluator implementation concern. Valid I'm sure, but does it bring any clarity for the user who authors a query?

- thomas