feat(furc): introduce while loop statement

Refs: #2

furc/include/furc/ast/fwd.hpp

@@ -235,7 +235,13 @@ using compound_statement_node_p =
 
 using compound_statement_node_r = node_r<compound_statement_node>; /**< Alias for compound_statement_node result */
 
+class while_statement_node;
+
+using while_statement_node_p = node_p<while_statement_node>; /**< Alias for a shared pointer to while_statement_node. */
+
+using while_statement_node_r = node_r<while_statement_node>; /**< Alias for while_statement_node result */
+
 } // namespace ast
 } // namespace furc
 
-#endif // FURC_AST_FWD_HPP
+#endif // FURC_AST_FWD_HPP

furc/include/furc/ast/statement.hpp

@@ -1,6 +1,7 @@
 #ifndef FURC_AST_STATEMENT_HPP
 #define FURC_AST_STATEMENT_HPP
 
+#include "furc/ast/fwd.hpp"
 #include "furc/ast/node.hpp"
 
 #include <optional>
@@ -17,6 +18,7 @@ enum class statement_node_t {
     Return,      /**< Return statement */
     If,          /**< If statement */
     Compound,    /**< Compound statement */
+    While,       /**< While loop statement. */
 };
 
 /**
@@ -191,7 +193,52 @@ private:
     struct body m_body; /**< The body handle. */
 };
 
+/**
+ * @brief while statement AST node.
+ */
+class while_statement_node final : public statement_node, public abstract_node {
+public:
+    /**
+     * @brief Construct a new while statement AST node.
+     *
+     * @param location Node location.
+     * @param body Body handle.
+     */
+    while_statement_node(struct location location, expression_node_p&& cond, statement_node_p&& body)
+      : abstract_node(location), m_cond(std::move(cond)), m_body(std::move(body)) {}
+public:
+    /**
+     * @brief Returns this node's condition expression.
+     *
+     * @return The condition expression.
+     */
+    const expression_node_p& condition() const { return m_cond; }
+
+    /**
+     * @brief Returns this node's body handle.
+     *
+     * @return The body handle.
+     */
+    const statement_node_p& body() const { return m_body; }
+public:
+    /**
+     * @brief Returns this node's statement type.
+     *
+     * @return statement_node_t::while.
+     */
+    statement_node_t statement_type() const override { return statement_node_t::While; }
+public:
+    void accept(visitor& visitor) const override;
+
+    std::ostream& print(std::ostream& os) const override;
+protected:
+    bool equal(const node& rhs) const override;
+private:
+    expression_node_p m_cond; /**< The condition expression. */
+    statement_node_p  m_body; /**< The body handle. */
+};
+
 } // namespace ast
 } // namespace furc
 
-#endif // FURC_AST_STATEMENT_HPP
+#endif // FURC_AST_STATEMENT_HPP

furc/include/furc/ast/visitor.hpp

@@ -122,6 +122,14 @@ public:
      */
     virtual void visit(const compound_statement_node& node) {}
 
+    /**
+     * @brief Visit a while_statement_node.
+     * @see while_statement_node
+     *
+     * @param node Node.
+     */
+    virtual void visit(const while_statement_node& node) {}
+
     /**
      * @brief Visit an AST error.
      *
@@ -133,4 +141,4 @@ public:
 } // namespace ast
 } // namespace furc
 
-#endif // FURC_AST_VISITOR_HPP
+#endif // FURC_AST_VISITOR_HPP

furc/include/furc/front/ir_generator.hpp

@@ -27,6 +27,7 @@ public:
     void visit(const ast::function_definition_node& funcDef) override;
     void visit(const ast::return_statement_node& returnStmt) override;
     void visit(const ast::if_statement_node& node) override;
+    void visit(const ast::while_statement_node& node) override;
     void visit(const ast::compound_statement_node& node) override;
     void visit(const ast::string_literal_node& node) override;
     void visit(const ast::integer_literal_node& node) override;
@@ -42,7 +43,7 @@ private:
         }
     }
 
-    furlang::ir::block_index push_block();
+    furlang::ir::block_index push_block(bool validate = true);
 private:
     furlang::ir::module                    m_module;
     std::unique_ptr<furlang::ir::function> m_currentFunction;
@@ -55,4 +56,4 @@ private:
 } // namespace front
 } // namespace furc
 
-#endif // FURC_FRONT_IR_GENERATOR_HPP
+#endif // FURC_FRONT_IR_GENERATOR_HPP

furc/include/furc/front/token.hpp

@@ -145,6 +145,7 @@ enum class keyword_token {
     Return, /**< `return` */
     If,     /**< `if` */
     Else,   /**< `else` */
+    While,  /**< `while` */
 };
 
 static inline std::ostream& operator<<(std::ostream& os, keyword_token keyword) {
@@ -154,6 +155,7 @@ static inline std::ostream& operator<<(std::ostream& os, keyword_token keyword)
     case keyword_token::Return: return os << "return";
     case keyword_token::If: return os << "if";
     case keyword_token::Else: return os << "else";
+    case keyword_token::While: return os << "while";
     }
     return os;
 }
@@ -165,6 +167,7 @@ static inline std::string operator+(const std::string& str, keyword_token keywor
     case keyword_token::Return: return str + "return";
     case keyword_token::If: return str + "if";
     case keyword_token::Else: return str + "else";
+    case keyword_token::While: return str + "while";
     }
     return str;
 }
@@ -377,4 +380,4 @@ using token_r = furlang::result<token, token_error>; /**< Alias to a token resul
 } // namespace front
 } // namespace furc
 
-#endif // FURC_FRONT_TOKEN_HPP
+#endif // FURC_FRONT_TOKEN_HPP