From e5513d7bcfaeb2a32c9b8af26af7e26c78166bf1 Mon Sep 17 00:00:00 2001
From: collin <collin.chin@berkeley.edu>
Date: Thu, 30 Apr 2020 10:34:49 -0700
Subject: [PATCH] add exponentiation assignment

---
 benchmark/simple.leo       |  2 +-
 compiler/src/ast.rs        | 65 ++++++++++++++++++++------------------
 compiler/src/leo.pest      |  6 ++--
 compiler/src/types_from.rs |  7 ++++
 4 files changed, 46 insertions(+), 34 deletions(-)

diff --git a/benchmark/simple.leo b/benchmark/simple.leo
index 54945d6b66..3ad5b9cb03 100644
--- a/benchmark/simple.leo
+++ b/benchmark/simple.leo
@@ -1,5 +1,5 @@
 function main() -> (u32) {
   a = 2;
-  a /= 3;
+  a **= 3;
   return a
 }
\ No newline at end of file
diff --git a/compiler/src/ast.rs b/compiler/src/ast.rs
index 6406f27d66..777bdab1a9 100644
--- a/compiler/src/ast.rs
+++ b/compiler/src/ast.rs
@@ -89,6 +89,41 @@ pub enum BinaryOperator {
     Pow,
 }
 
+#[derive(Clone, Debug, FromPest, PartialEq)]
+#[pest_ast(rule(Rule::assign))]
+pub struct Assign {}
+
+#[derive(Clone, Debug, FromPest, PartialEq)]
+#[pest_ast(rule(Rule::operation_add_assign))]
+pub struct AddAssign {}
+
+#[derive(Clone, Debug, FromPest, PartialEq)]
+#[pest_ast(rule(Rule::operation_sub_assign))]
+pub struct SubAssign {}
+
+#[derive(Clone, Debug, FromPest, PartialEq)]
+#[pest_ast(rule(Rule::operation_mul_assign))]
+pub struct MulAssign {}
+
+#[derive(Clone, Debug, FromPest, PartialEq)]
+#[pest_ast(rule(Rule::operation_div_assign))]
+pub struct DivAssign {}
+
+#[derive(Clone, Debug, FromPest, PartialEq)]
+#[pest_ast(rule(Rule::operation_pow_assign))]
+pub struct PowAssign {}
+
+#[derive(Clone, Debug, FromPest, PartialEq)]
+#[pest_ast(rule(Rule::operation_assign))]
+pub enum OperationAssign {
+    Assign(Assign),
+    AddAssign(AddAssign),
+    SubAssign(SubAssign),
+    MulAssign(MulAssign),
+    DivAssign(DivAssign),
+    PowAssign(PowAssign),
+}
+
 // Types
 
 #[derive(Clone, Debug, FromPest, PartialEq)]
@@ -851,36 +886,6 @@ pub struct DefinitionStatement<'ast> {
     pub span: Span<'ast>,
 }
 
-#[derive(Clone, Debug, FromPest, PartialEq)]
-#[pest_ast(rule(Rule::assign))]
-pub struct Assign {}
-
-#[derive(Clone, Debug, FromPest, PartialEq)]
-#[pest_ast(rule(Rule::operation_add_assign))]
-pub struct AddAssign {}
-
-#[derive(Clone, Debug, FromPest, PartialEq)]
-#[pest_ast(rule(Rule::operation_sub_assign))]
-pub struct SubAssign {}
-
-#[derive(Clone, Debug, FromPest, PartialEq)]
-#[pest_ast(rule(Rule::operation_mul_assign))]
-pub struct MulAssign {}
-
-#[derive(Clone, Debug, FromPest, PartialEq)]
-#[pest_ast(rule(Rule::operation_div_assign))]
-pub struct DivAssign {}
-
-#[derive(Clone, Debug, FromPest, PartialEq)]
-#[pest_ast(rule(Rule::operation_assign))]
-pub enum OperationAssign {
-    Assign(Assign),
-    AddAssign(AddAssign),
-    SubAssign(SubAssign),
-    MulAssign(MulAssign),
-    DivAssign(DivAssign),
-}
-
 #[derive(Clone, Debug, FromPest, PartialEq)]
 #[pest_ast(rule(Rule::statement_assign))]
 pub struct AssignStatement<'ast> {
diff --git a/compiler/src/leo.pest b/compiler/src/leo.pest
index 4409bca335..d7104f3619 100644
--- a/compiler/src/leo.pest
+++ b/compiler/src/leo.pest
@@ -44,11 +44,11 @@ operation_add_assign = { "+=" }
 operation_sub_assign = { "-=" }
 operation_mul_assign = { "*=" }
 operation_div_assign = { "/=" }
+operation_pow_assign = { "**=" }
 
 operation_assign = {
-    assign
-    | operation_add_assign | operation_sub_assign
-    | operation_mul_assign | operation_div_assign
+    assign | operation_add_assign | operation_sub_assign |
+    operation_mul_assign | operation_div_assign | operation_pow_assign
 }
 
 /// Types
diff --git a/compiler/src/types_from.rs b/compiler/src/types_from.rs
index 2ed957757f..17ea33f3e9 100644
--- a/compiler/src/types_from.rs
+++ b/compiler/src/types_from.rs
@@ -420,6 +420,13 @@ impl<'ast, F: Field + PrimeField> From<ast::AssignStatement<'ast>> for types::St
                             Box::new(types::Expression::from(statement.expression)),
                         ),
                     ),
+                    ast::OperationAssign::PowAssign(ref _assign) => types::Statement::Assign(
+                        types::Assignee::from(statement.assignee),
+                        types::Expression::Pow(
+                            Box::new(converted),
+                            Box::new(types::Expression::from(statement.expression)),
+                        ),
+                    ),
                     ast::OperationAssign::Assign(ref _assign) => {
                         unimplemented!("cannot assign twice to assign statement")
                     }