Scheduler additions

• Adds support for else if
• Adds boolean operators not (!), or (||), and and (&&)

juno_scheduler/src/lang.y

@@ -6,6 +6,9 @@
 %left '\\'
 %left '|'
 %left '&'
+%left '||'
+%left '&&'
+%right '!'
 %left '.' '@'
 
 %%
@@ -27,14 +30,23 @@ Stmt -> Stmt
       { Stmt::ExprStmt { span: $span, exp: $1 } }
   | 'fixpoint' FixpointLimit '{' Schedule '}'
       { Stmt::Fixpoint { span: $span, limit: $2, body: Box::new($4) } }
-  | 'if' Expr '{' Schedule '}'
-      { Stmt::IfThenElse { span: $span, cond: $2, thn: Box::new($4), els: None } }
-  | 'if' Expr '{' Schedule '}' 'else' '{' Schedule '}'
-      { Stmt::IfThenElse { span: $span, cond: $2, thn: Box::new($4), els: Some(Box::new($8)) } }
+  | 'if' Expr '{' Schedule '}' ElseStmt
+      { Stmt::IfThenElse { span: $span, cond: $2, thn: Box::new($4), els: $6 } }
   | MacroDecl
       { Stmt::MacroDecl { span: $span, def: $1 } }
   ;
 
+ElseStmt -> Option<Box<OperationList>>
+  :   { None }
+  | 'else' '{' Schedule '}'
+      { Some(Box::new($3)) }
+  | 'else' 'if' Expr '{' Schedule '}' ElseStmt
+      { Some(Box::new(OperationList::ConsStmt(
+          Stmt::IfThenElse { span: $span, cond: $3, thn: Box::new($5), els: $7 },
+          Box::new(OperationList::NilStmt()),
+        ))) }
+  ;
+
 FixpointLimit -> FixpointLimit
   : { FixpointLimit::NoLimit { span: $span } }
   | 'stop_after' 'INT'
@@ -75,11 +87,17 @@ Expr -> Expr
   | '<' Fields '>'
       { Expr::Record { span: $span, fields: rev($2) } }
   | Expr '\\' Expr
-      { Expr::SetOp { span: $span, op: SetOp::Difference, lhs: Box::new($1), rhs: Box::new($3) } }
+      { Expr::BinaryOp { span: $span, op: BinaryOp::Difference, lhs: Box::new($1), rhs: Box::new($3) } }
   | Expr '|' Expr
-      { Expr::SetOp { span: $span, op: SetOp::Union, lhs: Box::new($1), rhs: Box::new($3) } }
+      { Expr::BinaryOp { span: $span, op: BinaryOp::Union, lhs: Box::new($1), rhs: Box::new($3) } }
   | Expr '&' Expr
-      { Expr::SetOp { span: $span, op: SetOp::Intersection, lhs: Box::new($1), rhs: Box::new($3) } }
+      { Expr::BinaryOp { span: $span, op: BinaryOp::Intersection, lhs: Box::new($1), rhs: Box::new($3) } }
+  | '!' Expr
+      { Expr::UnaryOp { span: $span, op: UnaryOp::Not, exp: Box::new($2) } }
+  | Expr '||' Expr
+      { Expr::BinaryOp { span: $span, op: BinaryOp::Or, lhs: Box::new($1), rhs: Box::new($3) } }
+  | Expr '&&' Expr
+      { Expr::BinaryOp { span: $span, op: BinaryOp::And, lhs: Box::new($1), rhs: Box::new($3) } }
   ;
 
 Args -> Vec<Expr>
@@ -179,10 +197,17 @@ pub enum FixpointLimit {
 }
 
 #[derive(Copy, Clone, Debug)]
-pub enum SetOp {
+pub enum UnaryOp {
+  Not,
+}
+
+#[derive(Copy, Clone, Debug)]
+pub enum BinaryOp {
   Difference,
   Union,
   Intersection,
+  Or,
+  And,
 }
 
 pub enum Expr {
@@ -195,7 +220,8 @@ pub enum Expr {
   Field       { span: Span, lhs: Box<Expr>, field: Span },
   BlockExpr   { span: Span, body: Box<OperationList> },
   Record      { span: Span, fields: Vec<(Span, Expr)> },
-  SetOp       { span: Span, op: SetOp, lhs: Box<Expr>, rhs: Box<Expr> },
+  UnaryOp     { span: Span, op: UnaryOp, exp: Box<Expr> },
+  BinaryOp    { span: Span, op: BinaryOp, lhs: Box<Expr>, rhs: Box<Expr> },
   Tuple       { span: Span, exps: Vec<Expr> },
   TupleField  { span: Span, lhs: Box<Expr>, field: Span },
 }