returnData context

[frontier159]

gm @Rubilmax this is cool.

I see you added Placeholder which hasn't explicitly been described in the README, to allow the updating of calldata placeholders inline for a given step, using the result of a staticcall.

Have you also considered being able to use the same idea for the result of step i returnData to update a callData placeholder of step i+1? Any reason not to do that? Perhaps also using transient storage?

Also a general question: I see the new Morpho liquidation bot uses this, and not the Morpho Bundler3. Would you (or maybe @tomrpl) know the reasons for that, and would this be the approach you would use going forward rather than Bundler3?

[Rubilmax]

Hi! I'll document the use of Placeholders asap!

Do you have a specific use case where you need to use the reoslut of a previous CALL in a current CALL, which cannot be fetched using any other STATICCALL?

I did not do anticipate this use case because I thought that any return value of an onchain function should be able to be recalculated onchain, maybe at the cost of an additional "lens" contract deployed specifically for the use case

As for your second question, here's how I see things: I would always go forward with the Executor for personal use cases because I don't have to care about safety of the assets moved through it, as it is permissioned Bundler3 is only transiently permissioned and as such is better suited for shared, single transaction application actions

[frontier159]

Do you have a specific use case where you need to use the reoslut of a previous CALL in a current CALL, which cannot be fetched using any other STATICCALL?

I think most scenarios I can think of it would be possible with a STATICCALL, although there may well be gas overhead (sometimes significant?) with this. Not just an additional lens contract, but also runtime gas to do the STATICCALL.

I guess there could be some case of multiple swaps, followed by some action where you didn't just want to use the token.balanceOf(address(this)). Or perhaps just that there isn't a public function to query the intended state (but was part of the returndata). Just theorising though - I dont have a concrete example.

Makes sense that Bundler3 is setup as a singleton for shared use, whereas this is for personal use 👍