ast: add continue expression

src/ast.rs

@@ -354,6 +354,7 @@ impl<A: Annotation> Display for Expr<A> {
             Self::Bind(v) => v.fmt(f),
             Self::Make(v) => v.fmt(f),
 
+            Self::Op(op @ Op::Continue, exprs) => f.delimit(op, "").list(exprs, "!?,"),
             Self::Op(op @ (Op::If | Op::While), exprs) => match exprs.as_slice() {
                 [cond, pass, Anno(Expr::Op(Op::Tuple, e), _)] if e.is_empty() => {
                     write!(f, "{op}{cond} {pass}")

src/lexer.rs

@@ -292,6 +292,7 @@ impl<'t> Lexer<'t> {
                 "as" => TKind::As,
                 "break" => TKind::Break,
                 "const" => TKind::Const,
+                "continue" => TKind::Continue,
                 "do" => TKind::Do,
                 "else" => TKind::Else,
                 "enum" => TKind::Enum,

src/parser/expr.rs

@@ -120,6 +120,7 @@ fn from_prefix(token: &Token) -> PResult<(Ps, Prec)> {
         TKind::While => (Ps::Op(Op::While), Prec::Body),
         TKind::Break => (Ps::Op(Op::Break), Prec::Body),
         TKind::Return => (Ps::Op(Op::Return), Prec::Body),
+        TKind::Continue => (Ps::Op(Op::Continue), Prec::Min),
 
         TKind::LCurly => (Ps::Op(Op::Block), Prec::Min),
         TKind::RCurly => (Ps::End, Prec::Do),
@@ -266,6 +267,7 @@ impl<'t> Parse<'t> for Expr {
                     Some(value) => Expr::Op(Op::Group, vec![value]),
                     None => Expr::Op(Op::Tuple, vec![]),
                 },
+                Ps::Op(Op::Continue) => p.consume().then(Expr::Op(Op::Continue, vec![])),
                 Ps::Op(op @ (Op::If | Op::While)) => {
                     p.consume();
                     let exprs = vec![

src/token.rs

@@ -67,6 +67,7 @@ pub enum TKind {
     As,
     Break,
     Const,
+    Continue,
     Do,
     Else,
     Enum,