Extend enter_region method (#5)

Author: 0xddom

Cargo.toml

@@ -5,7 +5,7 @@ members = [
 resolver = "2"
 
 [workspace.package]
-version = "0.2.0"
+version = "0.3.0"
 authors = ["Daniel Dominguez (Veridise) <daniel@veridise.com>"]
 edition = "2024"
 rust-version = "1.85"

core/src/synthesis.rs

@@ -5,7 +5,7 @@ use ff::Field;
 use crate::{
     info_traits::{GroupInfo, SelectorInfo},
     query::{Advice, Fixed},
-    table::{Any, Column},
+    table::{Any, Column, RegionIndex, RegionStart},
 };
 
 /// Unique identifier for a group.
@@ -17,8 +17,17 @@ pub type GroupKey = u64;
 pub trait SynthesizerLike<F: Field> {
     /// Enters a new region of the circuit.
     ///
+    /// If the region index and starting row is known at this point is better to give
+    /// this information now since it avoids having to infer the information from context clues
+    /// later.
+    ///
     /// Panics if the synthesizer entered a region already and didn't exit.
-    fn enter_region(&mut self, region_name: String);
+    fn enter_region(
+        &mut self,
+        region_name: String,
+        region_index: Option<RegionIndex>,
+        region_start: Option<RegionStart>,
+    );
 
     /// Exits the current region of the circuit.
     ///

core/src/table.rs

@@ -214,6 +214,24 @@ impl From<usize> for RegionIndex {
     }
 }
 
+/// Replacement for Halo2's `RegionStart` type.
+#[derive(Eq, Hash, PartialEq, Debug, Copy, Clone)]
+pub struct RegionStart(usize);
+
+impl Deref for RegionStart {
+    type Target = usize;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl From<usize> for RegionStart {
+    fn from(value: usize) -> Self {
+        Self(value)
+    }
+}
+
 /// Errors related to the PLONK table.
 #[derive(Error, Copy, Clone, Debug)]
 pub enum TableError {