add assert statement module

compiler/src/statement/assert/assert_eq.rs

@@ -0,0 +1,29 @@
+//! Enforces an assert equals statement in a compiled Leo program.
+
+use crate::{errors::StatementError, program::ConstrainedProgram, value::ConstrainedValue, GroupType};
+use leo_types::Span;
+
+use snarkos_models::{
+    curves::{Field, PrimeField},
+    gadgets::{
+        r1cs::ConstraintSystem,
+        utilities::{boolean::Boolean, eq::ConditionalEqGadget},
+    },
+};
+
+impl<F: Field + PrimeField, G: GroupType<F>> ConstrainedProgram<F, G> {
+    pub fn enforce_assert_eq_statement<CS: ConstraintSystem<F>>(
+        &mut self,
+        cs: &mut CS,
+        indicator: Option<Boolean>,
+        left: &ConstrainedValue<F, G>,
+        right: &ConstrainedValue<F, G>,
+        span: Span,
+    ) -> Result<(), StatementError> {
+        let condition = indicator.unwrap_or(Boolean::Constant(true));
+        let name_unique = format!("assert {} == {} {}:{}", left, right, span.line, span.start);
+        let result = left.conditional_enforce_equal(cs.ns(|| name_unique), right, &condition);
+
+        Ok(result.map_err(|_| StatementError::assertion_failed(left.to_string(), right.to_string(), span))?)
+    }
+}

compiler/src/statement/assert/mod.rs

@@ -0,0 +1,4 @@
+//! Methods to enforce constraints on assert statements in a Leo program.
+
+pub mod assert_eq;
+pub use self::assert_eq::*;

compiler/src/statement/iteration/iteration.rs

@@ -0,0 +1,66 @@
+//! Enforces an iteration statement in a compiled Leo program.
+
+use crate::{
+    errors::StatementError,
+    new_scope,
+    program::ConstrainedProgram,
+    value::ConstrainedValue,
+    GroupType,
+    Integer,
+};
+use leo_types::{Expression, Identifier, Span, Statement, Type};
+
+use snarkos_models::{
+    curves::{Field, PrimeField},
+    gadgets::{
+        r1cs::ConstraintSystem,
+        utilities::{boolean::Boolean, uint::UInt32},
+    },
+};
+
+impl<F: Field + PrimeField, G: GroupType<F>> ConstrainedProgram<F, G> {
+    pub fn enforce_iteration_statement<CS: ConstraintSystem<F>>(
+        &mut self,
+        cs: &mut CS,
+        file_scope: String,
+        function_scope: String,
+        indicator: Option<Boolean>,
+        index: Identifier,
+        start: Expression,
+        stop: Expression,
+        statements: Vec<Statement>,
+        return_types: Vec<Type>,
+        span: Span,
+    ) -> Result<Vec<(Option<Boolean>, ConstrainedValue<F, G>)>, StatementError> {
+        let mut results = vec![];
+
+        let from = self.enforce_index(cs, file_scope.clone(), function_scope.clone(), start, span.clone())?;
+        let to = self.enforce_index(cs, file_scope.clone(), function_scope.clone(), stop, span.clone())?;
+
+        for i in from..to {
+            // Store index in current function scope.
+            // For loop scope is not implemented.
+            let index_name = new_scope(function_scope.clone(), index.to_string());
+
+            self.store(
+                index_name,
+                ConstrainedValue::Integer(Integer::U32(UInt32::constant(i as u32))),
+            );
+
+            // Evaluate statements and possibly return early
+            let name_unique = format!("for loop iteration {} {}:{}", i, span.line, span.start);
+            let mut result = self.evaluate_branch(
+                &mut cs.ns(|| name_unique),
+                file_scope.clone(),
+                function_scope.clone(),
+                indicator,
+                statements.clone(),
+                return_types.clone(),
+            )?;
+
+            results.append(&mut result);
+        }
+
+        Ok(results)
+    }
+}

compiler/src/statement/iteration/mod.rs

@@ -0,0 +1,4 @@
+//! Methods to enforce constraints on iteration statements in a compiled Leo program.
+
+pub mod iteration;
+pub use self::iteration::*;

compiler/src/statement/mod.rs

@@ -1,3 +1,8 @@
+//! Methods to enforce constraints on statements in a Leo program.
+
+pub mod assert;
+pub use self::assert::*;
+
 pub mod assign;
 pub use self::assign::*;
 
@@ -10,6 +15,9 @@ pub use self::conditional::*;
 pub mod definition;
 pub use self::definition::*;
 
+pub mod iteration;
+pub use self::iteration::*;
+
 pub mod return_;
 pub use self::return_::*;
 

compiler/src/statement/statement.rs

@@ -1,89 +1,19 @@
 //! Methods to enforce constraints on statements in a compiled Leo program.
 
-use crate::{
-    errors::StatementError,
-    new_scope,
-    program::ConstrainedProgram,
-    value::ConstrainedValue,
-    GroupType,
-    Integer,
-};
-use leo_types::{Expression, Identifier, Span, Statement, Type};
+use crate::{errors::StatementError, program::ConstrainedProgram, value::ConstrainedValue, GroupType};
+use leo_types::{Statement, Type};
 
 use snarkos_models::{
     curves::{Field, PrimeField},
-    gadgets::{
-        r1cs::ConstraintSystem,
-        utilities::{boolean::Boolean, eq::ConditionalEqGadget, uint::UInt32},
-    },
+    gadgets::{r1cs::ConstraintSystem, utilities::boolean::Boolean},
 };
 
 impl<F: Field + PrimeField, G: GroupType<F>> ConstrainedProgram<F, G> {
-    fn enforce_for_statement<CS: ConstraintSystem<F>>(
-        &mut self,
-        cs: &mut CS,
-        file_scope: String,
-        function_scope: String,
-        indicator: Option<Boolean>,
-        index: Identifier,
-        start: Expression,
-        stop: Expression,
-        statements: Vec<Statement>,
-        return_types: Vec<Type>,
-        span: Span,
-    ) -> Result<Vec<(Option<Boolean>, ConstrainedValue<F, G>)>, StatementError> {
-        let mut results = vec![];
-
-        let from = self.enforce_index(cs, file_scope.clone(), function_scope.clone(), start, span.clone())?;
-        let to = self.enforce_index(cs, file_scope.clone(), function_scope.clone(), stop, span.clone())?;
-
-        for i in from..to {
-            // Store index in current function scope.
-            // For loop scope is not implemented.
-            let index_name = new_scope(function_scope.clone(), index.to_string());
-
-            self.store(
-                index_name,
-                ConstrainedValue::Integer(Integer::U32(UInt32::constant(i as u32))),
-            );
-
-            // Evaluate statements and possibly return early
-            let name_unique = format!("for loop iteration {} {}:{}", i, span.line, span.start);
-            let mut result = self.evaluate_branch(
-                &mut cs.ns(|| name_unique),
-                file_scope.clone(),
-                function_scope.clone(),
-                indicator,
-                statements.clone(),
-                return_types.clone(),
-            )?;
-
-            results.append(&mut result);
-        }
-
-        Ok(results)
-    }
-
-    fn enforce_assert_eq_statement<CS: ConstraintSystem<F>>(
-        &mut self,
-        cs: &mut CS,
-        indicator: Option<Boolean>,
-        left: &ConstrainedValue<F, G>,
-        right: &ConstrainedValue<F, G>,
-        span: Span,
-    ) -> Result<(), StatementError> {
-        let condition = indicator.unwrap_or(Boolean::Constant(true));
-        let name_unique = format!("assert {} == {} {}:{}", left, right, span.line, span.start);
-        let result = left.conditional_enforce_equal(cs.ns(|| name_unique), right, &condition);
-
-        Ok(result.map_err(|_| StatementError::assertion_failed(left.to_string(), right.to_string(), span))?)
-    }
-
     /// Enforce a program statement.
     /// Returns a Vector of (indicator, value) tuples.
     /// Each evaluated statement may execute of one or more statements that may return early.
     /// To indicate which of these return values to take we conditionally select that value with the indicator bit.
-    pub(crate) fn enforce_statement<CS: ConstraintSystem<F>>(
+    pub fn enforce_statement<CS: ConstraintSystem<F>>(
         &mut self,
         cs: &mut CS,
         file_scope: String,
@@ -124,8 +54,8 @@ impl<F: Field + PrimeField, G: GroupType<F>> ConstrainedProgram<F, G> {
 
                 results.append(&mut result);
             }
-            Statement::For(index, start, stop, statements, span) => {
-                let mut result = self.enforce_for_statement(
+            Statement::Iteration(index, start, stop, statements, span) => {
+                let mut result = self.enforce_iteration_statement(
                     cs,
                     file_scope,
                     function_scope,

types/src/statements/statement.rs

@@ -25,7 +25,7 @@ pub enum Statement {
     MultipleDefinition(Vec<Variable>, Expression, Span),
     Assign(Assignee, Expression, Span),
     Conditional(ConditionalStatement, Span),
-    For(Identifier, Expression, Expression, Vec<Statement>, Span),
+    Iteration(Identifier, Expression, Expression, Vec<Statement>, Span),
     AssertEq(Expression, Expression, Span),
     Expression(Expression, Span),
 }
@@ -154,7 +154,7 @@ impl<'ast> From<MultipleAssignmentStatement<'ast>> for Statement {
 
 impl<'ast> From<ForStatement<'ast>> for Statement {
     fn from(statement: ForStatement<'ast>) -> Self {
-        Statement::For(
+        Statement::Iteration(
             Identifier::from(statement.index),
             Expression::from(statement.start),
             Expression::from(statement.stop),
@@ -237,7 +237,7 @@ impl fmt::Display for Statement {
                 write!(f, ") = {};", function)
             }
             Statement::Conditional(ref statement, ref _span) => write!(f, "{}", statement),
-            Statement::For(ref var, ref start, ref stop, ref list, ref _span) => {
+            Statement::Iteration(ref var, ref start, ref stop, ref list, ref _span) => {
                 write!(f, "for {} in {}..{} {{\n", var, start, stop)?;
                 for l in list {
                     write!(f, "\t\t{}\n", l)?;