added the parsing of expression statements

src/ast/statements/expression.cpp

@@ -0,0 +1,16 @@
+#include "expression.hpp"
+
+namespace ast {
+
+    expression_stmt::expression_stmt(token::token token)
+        : token(std::move(token)),
+          expression(nullptr) {}
+
+    std::string expression_stmt::token_literal() const {
+        return token.literal;
+    }
+
+    expression_stmt::~expression_stmt() {
+        delete expression;
+    }
+} // namespace ast

src/ast/statements/expression.hpp

@@ -0,0 +1,15 @@
+#include "ast/ast.hpp"
+#include "token/token.hpp"
+
+namespace ast {
+    struct expression_stmt : statement {
+        expression_stmt(token::token token);
+
+        token::token token;
+        ast::expression* expression;
+
+        std::string token_literal() const override;
+
+        ~expression_stmt();
+    };
+} // namespace ast

src/parser/parser.cpp

@@ -42,14 +42,6 @@ namespace parser {
         }
     }
 
-    bool parser::expect_next(token::type t) {
-        if (next.type == t) {
-            next_token();
-            return true;
-        }
-        next_error(t);
-        return false;
-    }
     ast::expression* parser::parse_expression() {
         // TODO: we are currently skipping expressions until we encounter a
         // semicolon
@@ -85,7 +77,21 @@ namespace parser {
         return stmt;
     }
 
+    ast::expression_stmt* parser::parse_expression_stmt() {
+        ast::expression_stmt* stmt = new ast::expression_stmt(current);
+
+        stmt->expression = parse_expression();
+
         return stmt;
+    };
+
+    bool parser::expect_next(token::type t) {
+        if (next.type == t) {
+            next_token();
+            return true;
+        }
+        next_error(t);
+        return false;
     }
 
     void parser::next_error(token::type t) {

src/parser/parser.hpp

@@ -2,6 +2,7 @@
 
 #include "ast/ast.hpp"
 #include "ast/errors/error.hpp"
+#include "ast/statements/expression.hpp"
 #include "ast/statements/let.hpp"
 #include "ast/statements/return.hpp"
 #include "lexer/lexer.hpp"
@@ -24,6 +25,7 @@ namespace parser {
         ast::expression* parse_expression();
         ast::let_stmt* parse_let();
         ast::return_stmt* parse_return();
+        ast::expression_stmt* parse_expression_stmt();
         bool expect_next(token::type);
         void next_error(token::type);
     };