document which lifetime is needed for systemparam derive

[laundmo]

Objective

Document a few common cases of which lifetime is required when using SystemParam Derive

Solution

Added a table in the doc comment

[alice-i-cecile]

Great idea to document, but I think this will be a lot more robust as a doc test.

[Nilirad]

Great idea to document, but I think this will be a lot more robust as a doc test.

I agree, actual doc examples are more useful and less prone to desync. Also, the user can obtain the lifetime parameters from the specific SystemParam they're interested in.

[laundmo]

Hope this is somewhat like you imagined? didn't want to make it visibly a codeblock, as there already is a example there. sadly no way to preserve table formatting during this... alas.

[laundmo]

looks like this now

[Nilirad]

Looks good enough. Not comprehensive, but sufficiently covers the most important cases. Ultimately, lifetimes can still be seen on the struct docs of the specific SystemParam.

[laundmo]

Looks good enough. Not comprehensive, but sufficiently covers the most important cases. Ultimately, lifetimes can still be seen on the struct docs of the specific SystemParam.

yeah that they're available elsewhere is exactly ehy i didnt include all of them