[fine] While loops, nothing

fine/src/parser.rs

@@ -143,10 +143,14 @@ pub enum TreeKind {
     ListConstructor,
     ListConstructorElement,
     LiteralExpression,
+    MatchArm,
+    MatchBody,
+    MatchExpression,
     MemberAccess,
     NewObjectExpression,
     ParamList,
     Parameter,
+    Pattern,
     ReturnStatement,
     ReturnType,
     SelfParameter,
@@ -156,13 +160,8 @@ pub enum TreeKind {
     TypeParameter,
     TypeParameterList,
     UnaryExpression,
-
-    Pattern,
     VariableBinding,
-
-    MatchExpression,
-    MatchBody,
-    MatchArm,
+    WhileStatement,
     WildcardPattern,
 }
 
@@ -781,6 +780,7 @@ const STATEMENT_RECOVERY: &[TokenKind] = &[
     TokenKind::Return,
     TokenKind::For,
     TokenKind::Class,
+    TokenKind::While,
 ];
 
 fn block(p: &mut CParser) {
@@ -813,6 +813,8 @@ fn statement(p: &mut CParser) -> bool {
         // require a semicolon at the end if it's all by itself.
         TokenKind::If => statement_if(p),
 
+        TokenKind::While => statement_while(p),
+
         _ => {
             if p.at(TokenKind::Semicolon) || p.at_any(EXPRESSION_FIRST) {
                 statement_expression(p)
@@ -834,6 +836,24 @@ fn statement_if(p: &mut CParser) {
     p.end(m, TreeKind::IfStatement);
 }
 
+fn statement_while(p: &mut CParser) {
+    let m = p.start();
+
+    p.expect_start(TokenKind::While);
+    if p.at_any(EXPRESSION_FIRST) {
+        expression(p);
+    } else {
+        p.error("expected an expression for the loop condition");
+    }
+    if p.at(TokenKind::LeftBrace) {
+        block(p);
+    } else {
+        p.error("expected a block for the loop body");
+    }
+
+    p.end(m, TreeKind::WhileStatement);
+}
+
 fn statement_let(p: &mut CParser) {
     let m = p.start();