Provide proper examples/docs for dynamic

[bkchr]

I'm currently using the dynamic instantiation stuff to create transactions, but it is a pain in the ass to figure out how to construct certain transactions. Today it took me quite a lot of time to find out how to properly construct a transfer_allow_death transaction, because encoding the dest parameter is kind of complicated. It would be nice if there are more examples and docs around the dynamic api.

[jsdw]

Yup for sure; actually building dynamic values isn't well documented!

If you haven't seen it, this macro may be particularly useful (in theory you can use any type with the dynamic stuff in subxt but in practice this is the scale_value::Value type is the one that is used):

https://docs.rs/scale-value/latest/scale_value/macro.value.html
another similar/tiny example of it: https://github.com/paritytech/scale-value/blob/main/examples/value_macro.rs

We should add better docs in scale-value for this macro especially and then link them from subxt

[bkchr]

Yes, I'm already using the value! macro. I was actually blocked by trying to do a transfer, because the destination decoding always failed :P This was because of the MultiAddress::Id and I did not realized this, because also the error message was confusing etc :D Some nice little quest :P

[jsdw]

I tweaked the docs of the macro to hopefully help on that side: https://docs.rs/scale-value/latest/scale_value/macro.value.html

But sounds like the other part of the issue is error messages which we can take a look at and see how easily we can make them better!