Global variables outside expressions like filter, sort, group, etc.

[hoangbn]

Is there a way I can assign "global" variables in a task query that I can then reuse inside each expression?

My main use case for this would be for caching: say I have some fairly costly function that uses query, and I want the result of it in an expression like filter. Right now, I could just make the calculation inside the filter expression, but this will be computed many, many times. I want to calculate it once outside, then reference it within the filter expression (or calculate it once for the first task inside the filter expression, but then reference it on subsequent tasks)

Another use case example, I want to define a global map variable that I can read and write to inside filter expression

[claremacrae]

No there is nothing built in.
Some people use the CustomJS plugin to have custom filter logic in one place - you can search this vault for CustomJs to find references to that.

But ca you give an example of a calculation that you feel is costly?

Normally the filter cost is negligible compared to task results rendering time.