add atid operation

include/inja/function_storage.hpp

@@ -36,6 +36,7 @@ public:
     Division,
     Power,
     Modulo,
+    AtId,
     At,
     Default,
     DivisibleBy,

include/inja/lexer.hpp

@@ -108,6 +108,8 @@ class Lexer {
       return make_token(Token::Kind::Power);
     case '%':
       return make_token(Token::Kind::Percent);
+    case '.':
+      return make_token(Token::Kind::Dot);
     case ',':
       return make_token(Token::Kind::Comma);
     case ':':

include/inja/node.hpp

@@ -141,7 +141,7 @@ public:
   size_t number_args;
   CallbackFunction callback;
 
-  explicit FunctionNode(nonstd::string_view name, size_t pos) : ExpressionNode(pos), precedence(5), associativity(Associativity::Left), operation(Op::Callback), name(name), number_args(1) { }
+  explicit FunctionNode(nonstd::string_view name, size_t pos) : ExpressionNode(pos), precedence(8), associativity(Associativity::Left), operation(Op::Callback), name(name), number_args(1) { }
   explicit FunctionNode(Op operation, size_t pos) : ExpressionNode(pos), operation(operation), number_args(1) {
     switch (operation) {
       case Op::Not: {
@@ -208,6 +208,10 @@ public:
         precedence = 4;
         associativity = Associativity::Left;
       } break;
+      case Op::AtId: {
+        precedence = 8;
+        associativity = Associativity::Left;
+      } break;
       default: {
         precedence = 1;
         associativity = Associativity::Left;

include/inja/parser.hpp

@@ -166,7 +166,8 @@ class Parser {
       case Token::Kind::Times:
       case Token::Kind::Slash:
       case Token::Kind::Power:
-      case Token::Kind::Percent: {
+      case Token::Kind::Percent:
+      case Token::Kind::Dot: {
 
   parse_operator:
         FunctionStorage::Operation operation;
@@ -220,6 +221,9 @@ class Parser {
         case Token::Kind::Percent: {
           operation = FunctionStorage::Operation::Modulo;
         } break;
+        case Token::Kind::Dot: {
+          operation = FunctionStorage::Operation::AtId;
+        } break;
         default: {
           throw_parser_error("unknown operator in parser.");
         }

include/inja/renderer.hpp

@@ -311,6 +311,16 @@ class Renderer : public NodeVisitor  {
       json_tmp_stack.push_back(result_ptr);
       json_eval_stack.push(result_ptr.get());
     } break;
+    case Op::AtId: {
+      json_eval_stack.pop(); // Pop id nullptr
+      auto container = get_arguments<1, false>(node)[0];
+      if (not_found_stack.empty()) {
+        throw_renderer_error("could not find element with given name", node);
+      }
+      auto id_node = not_found_stack.top();
+      not_found_stack.pop();
+      json_eval_stack.push(&container->at(id_node->name));
+    } break;
     case Op::At: {
       auto args = get_arguments<2>(node);
       json_eval_stack.push(&args[0]->at(args[1]->get<int>()));

include/inja/token.hpp

@@ -33,6 +33,7 @@ struct Token {
     Percent,            // %
     Power,              // ^
     Comma,              // ,
+    Dot,                // .
     Colon,              // :
     LeftParen,          // (
     RightParen,         // )