Expression macros

[Brechtpd]

Boolean logic macro:

bool!((selectorA && !selectorB) || selectorC)

-> generate:

or::expr([and::expr([selectorA.expr(), not::expr(selectorB.expr())]), selectorC.expr()])

[SuccinctPaul]

Hi, I've finished a demo, whitch can do bool!((a && !b) || c) -> Or[And([a, Not(b)]), c]). And it's tested.

You can see more https://github.com/privacy-scaling-explorations/zkevm-circuits/commit/3d78844d6dc3cd8c38908e82c65ebddd64c16f57

bool!((selectorA && !selectorB) || selectorC)-> or::expr([and::expr([selectorA.expr(), not::expr(selectorB.expr())]), selectorC.expr()])

And I've finished most for the above version. The last step is its test, which blocks me.

Do you have any suggestions?

See more one https://github.com/privacy-scaling-explorations/zkevm-circuits/commit/0f7ed0e770e11bd1274e1eeeb9f5f7577c6ff44a

[Brechtpd]

I totally missed this, very sorry about that!

This looks great, will try it out when I have some time. Thanks!

[johntaiko]

~~@ChengYueJia could you give us a PR regarding these changes? The code seems fine, but the naming could use some improvement. Additionally, I am available to assist with completing the testing phase if needed.~~

If our bool expression is complex enough, exhaustive enumeration is not a good solution. Here I recommend using Rust function-like procedural macros to build syntax trees and ultimately execute complex bool expressions.

[johntaiko]

#[proc_macro]
pub fn r#bool(item: TokenStream) -> TokenStream {
    // parse tokens to AST tree and generate the halo2 expression based it
}