From 8e688474e11f3b01344da93d76009c0e0736820f Mon Sep 17 00:00:00 2001
From: siq1 <siqi@polyhedra.network>
Date: Sat, 2 Nov 2024 01:43:30 +0800
Subject: [PATCH] implement get random value api

---
 expander_compiler/src/frontend/api.rs     |  1 +
 expander_compiler/src/frontend/builder.rs | 10 ++++++++++
 2 files changed, 11 insertions(+)

diff --git a/expander_compiler/src/frontend/api.rs b/expander_compiler/src/frontend/api.rs
index 08b7f8a..d0bad08 100644
--- a/expander_compiler/src/frontend/api.rs
+++ b/expander_compiler/src/frontend/api.rs
@@ -41,6 +41,7 @@ pub trait BasicAPI<C: Config> {
         x: impl ToVariableOrValue<C::CircuitField>,
         y: impl ToVariableOrValue<C::CircuitField>,
     );
+    fn get_random_value(&mut self) -> Variable;
 }
 
 pub trait UnconstrainedAPI<C: Config> {
diff --git a/expander_compiler/src/frontend/builder.rs b/expander_compiler/src/frontend/builder.rs
index ca42c27..eba6748 100644
--- a/expander_compiler/src/frontend/builder.rs
+++ b/expander_compiler/src/frontend/builder.rs
@@ -288,6 +288,12 @@ impl<C: Config> BasicAPI<C> for Builder<C> {
         let diff = self.sub(x, y);
         self.assert_is_non_zero(diff);
     }
+
+    fn get_random_value(&mut self) -> Variable {
+        self.instructions
+            .push(SourceInstruction::ConstantLike(Coef::Random));
+        self.new_var()
+    }
 }
 
 // write macro rules for unconstrained binary op definition
@@ -436,6 +442,10 @@ impl<C: Config> BasicAPI<C> for RootBuilder<C> {
     ) {
         self.last_builder().assert_is_different(x, y)
     }
+
+    fn get_random_value(&mut self) -> Variable {
+        self.last_builder().get_random_value()
+    }
 }
 
 impl<C: Config> RootBuilder<C> {