while command

alib2cli/src/ast/command/WhileCommand.h

+#ifndef _CLI_WHILE_COMMAND_H_
+#define _CLI_WHILE_COMMAND_H_
+
+#include <ast/Command.h>
+#include <environment/Environment.h>
+#include <ast/Statement.h>
+#include <common/CastHelper.h>
+
+namespace cli {
+
+class WhileCommand : public Command {
+	std::unique_ptr < Expression > m_condition;
+	std::unique_ptr < Command > m_body;
+
+public:
+	WhileCommand ( std::unique_ptr < Expression > condition, std::unique_ptr < Command > body ) : m_condition ( std::move ( condition ) ), m_body ( std::move ( body ) ) {
+	}
+
+	CommandResult run ( Environment & environment ) const override {
+		CommandResult res = cli::CommandResult::OK;
+		while ( res == cli::CommandResult::OK ) {
+			std::shared_ptr < abstraction::Value > conditionResult = m_condition->translateAndEval ( environment );
+
+			std::shared_ptr < abstraction::Value > castedResult = abstraction::CastHelper::eval ( environment, conditionResult, "bool" );
+
+			if ( ! std::static_pointer_cast < abstraction::ValueHolderInterface < bool > > ( castedResult )->getValue ( ) )
+				break;
+
+			res = m_body->run ( environment );
+		}
+
+		return res;
+	}
+};
+
+} /* namespace cli */
+
+#endif /* _CLI_WHILE_COMMAND_H_ */

alib2cli/src/parser/Parser.cpp

@@ -34,6 +34,7 @@
 #include <ast/command/EvalCommand.h>
 #include <ast/command/InterpretCommand.h>
 #include <ast/command/IfCommand.h>
+#include <ast/command/WhileCommand.h>
 #include <ast/command/ReturnCommand.h>
 #include <ast/expression/BatchExpression.h>
@@ -369,7 +370,7 @@ std::unique_ptr < CommandList > Parser::block ( ) {
 }
 std::unique_ptr < Command > Parser::semicolon_command ( ) {
-	bool semicolonFreeCommand = check_nonreserved_kw ( "begin", "if" );
+	bool semicolonFreeCommand = check_nonreserved_kw ( "begin", "if", "while" );
 	std::unique_ptr < Command > res = command ( );
 	if ( ! semicolonFreeCommand )
 		match ( cli::Lexer::TokenType::SEMICOLON_SIGN );
@@ -510,6 +511,18 @@ std::unique_ptr < Command > Parser::command ( ) {
 		}
 		return std::make_unique < IfCommand > ( std::move ( condition ), std::move ( thenBranch ), std::move ( elseBranch ) );
+	} else if ( check_nonreserved_kw ( "while" ) ) {
+		if ( globalScope ( ) )
+			throw exception::CommonException ( "Statement not available in global scope." );
+		match_nonreserved_kw ( "while" );
+		match ( cli::Lexer::TokenType::LEFT_PAREN );
+		std::unique_ptr < Expression > condition = expression_or_batch ( );
+		match ( cli::Lexer::TokenType::RIGHT_PAREN );
+
+		match_nonreserved_kw ( "do" );
+		std::unique_ptr < Command > body = semicolon_command ( );
+
+		return std::make_unique < WhileCommand > ( std::move ( condition ), std::move ( body ) );
 	} else {
 		throw exception::CommonException ( "Mismatched set " + ext::to_string ( getCheckOptions ( ) ) + " while expanding parse rule. Token is " + ( ( std::string ) m_current ) + "." );
 	}