Move define_udt! decl macro to sol! proc macro

[DaniPopes]

core/crates/sol-types/src/types/udt.rs

Line 7 in 0c21fcc

macro_rules! define_udt {

[DaniPopes]

UDVTs in Solidity are just type aliases, so this should be the case in sol! too. This means that it should expand to type #name = #solidity_type; and any reference to it anywhere in the macro should be interpreted as the internal solidity type.

[prestwich]

same disagreement as Address vs FixedBytes<20>. In solidity its barely more than an alias, but it really isn't the same type. Suppose the user wants to add a custom impl block the way we do for Address. If UDTs are aliases, they can't do that. It also fails to prevent type confusion

[mahmudsudo]

can i take this ?

[mahmudsudo]

can some extra details of the usage be given ?

[DaniPopes]

can i take this ?

Sure, go ahead!

It's mostly just porting the macro_rules! to proc macro code using quote! in here:

core/crates/sol-macro/src/expand/udt.rs

Line 9 in 0c21fcc

pub(super) fn expand(cx: &ExpCtxt<'_>, udt: &ItemUdt) -> Result<TokenStream> {

You can look at the other files in the expand module for examples

[mahmudsudo]

would start on it immediately

[fgimenez]

@mahmudsudo are you working on this? if not I'd like to give it a try