add error contexts to other top levels

src/parsers.zig

@@ -518,11 +518,15 @@ pub const Parser = struct {
         var consts = ast.ConstList.init(self.allocator);
         errdefer consts.deinit();
 
+        self.setErrContext("const");
+
         _ = try self.consumeSingle(.Const);
         _ = try self.consumeSingle(.LeftParen);
 
         while (self.peek().typ != .RightParen) {
             const const_name = try self.consumeSingle(.Identifier);
+            self.setErrContext("const {}", const_name);
+
             _ = try self.consumeSingle(.Equal);
 
             // const declarations dont have type, a future type system must
@@ -537,18 +541,19 @@ pub const Parser = struct {
         }
 
         _ = try self.consumeSingle(.RightParen);
-
         return self.mkConstDecl(consts);
     }
 
     fn parseStructDecl(self: *@This()) !*Node {
         var fields = ast.FieldList.init(self.allocator);
         errdefer fields.deinit();
+        self.setErrContext("struct", name);
 
         _ = try self.consumeSingle(.Struct);
-
         var name = try self.consumeSingle(.Identifier);
 
+        self.setErrContext("struct {}", name);
+
         _ = try self.consumeSingle(.LeftBrace);
 
         var field_state = FieldState{};
@@ -557,6 +562,8 @@ pub const Parser = struct {
             try self.parseFieldModifiers(&field_state);
 
             const field_name = try self.consumeSingle(.Identifier);
+            self.setErrContext("struct {} field {}", name, field_name);
+
             const field_type = try self.consumeSingle(.Identifier);
 
             // we could create a FieldState on the heap and copy our current
@@ -624,13 +631,16 @@ pub const Parser = struct {
     }
 
     fn parseEnumDecl(self: *@This()) !*Node {
-        _ = try self.consumeSingle(.Enum);
-
         var fields = ast.TokenList.init(self.allocator);
         errdefer fields.deinit();
 
+        self.setErrContext("enum");
+
+        _ = try self.consumeSingle(.Enum);
         const name = try self.consumeSingle(.Identifier);
 
+        self.setErrContext("enum {}", name);
+
         _ = try self.consumeSingle(.LeftBrace);
 
         while (!self.check(.RightBrace)) {