public void Build()
{
while (_reader.HasNext())
{
_reader.Next();
var token = _reader.Current();
switch (token.TokenType)
{
case TokenType.Keyword:
if (_reader.Current().Value == Keywords.FOR)
{
var block = new ForBlockBuilder(_reader, _block).Build();
Block.Children.Add(block);
}
else if (_reader.Current().Value == Keywords.IF)
{
var block = new IfBlockBuilder(_reader, _block).Build();
Block.Children.Add(block);
}
else if (_reader.Current().Value == Keywords.FOREACH)
{
var block = new ForeachBuilder(_reader, _block).Build();
Block.Children.Add(block);
}
else if (_reader.Current().Value == Keywords.DO)
{
var block = new DoWhileScopeBuilder(_reader, _block).Build();
Block.Children.Add(block);
}
else if (_reader.Current().Value == Keywords.WHILE)
{
var block = new WhileBlockBuilder(_reader, _block).Build();
Block.Children.Add(block);
}
else if (_reader.Current().Value == Keywords.TRY)
{
var block = new TryCatchFinallyBlockBuilder(_reader, _block).Build();
Block.Children.Add(block);
}
else
{
throwError("");
}
break;
case TokenType.Operator:
switch (_reader.Current().OperatorType)
{
/*
* variable declare
*/
case OperatorType.Declare:
var decExpression = new DeclareExpressionBuilder(_reader, _block).Build();
Block.Children.Add(decExpression);
break;
/*
* Function define expression is all right in this scope
*
*/
case OperatorType.Function:
var function = new FunctionBuilder(_reader, _block).Build();
var funcDefineExp = new FunctionDefineExpression(_block);
funcDefineExp.Root = new FunctionDefineNode(_block);
funcDefineExp.Root.Operands.Add(new OperandNode(function));
Block.Children.Add(funcDefineExp);
break;
/*
* New expression
*/
case OperatorType.NewInstance:
/*
* Increament expression
*
*/
case OperatorType.Increment:
case OperatorType.Decrement:
_reader.Back();
var crementExpression = new ExpressionBuilder(_reader, false, _block).Build();
Block.Children.Add(crementExpression);
break;
/*
* Expression can not start with operator ,excepts increment(++) ,decrement(--) ,var ,new ,function
*
*/
default:
throwError("");
break;
}
break;
/*
* Back one token ,to build excuting expression
*
*/
case TokenType.Identifier:
_reader.Back();
var expression = new ExpressionBuilder(_reader, true, _block).Build();
Block.Children.Add(expression);
break;
/*
* Expression can not start with those kinds of token
* number,null,bool,string
*
*/
case TokenType.String:
case TokenType.Number:
case TokenType.Bool:
case TokenType.Null:
default:
throwError("");
break;
}
}
}
public OrderdedBlock Build()
{
OrderdedBlock orderingBlock = new OrderdedBlock(_block);
throwErrorIfHasNoNextOrNext($"incompleted {_parentName} block;");
/*
* to check ,the block is single expression or mutiple expression
*
*/
if (_reader.Current().OperatorType == OperatorType.LeftBrace)
{
while (_reader.HasNext())
{
_reader.Next();
var token = _reader.Current();
switch (token.TokenType)
{
case TokenType.Keyword:
if (_reader.Current().Value == Keywords.FOR)
{
var block = new ForBlockBuilder(_reader, orderingBlock).Build();
orderingBlock.Children.Add(block);
}
else if (_reader.Current().Value == Keywords.IF)
{
var block = new IfBlockBuilder(_reader, orderingBlock).Build();
orderingBlock.Children.Add(block);
}
else if (_reader.Current().Value == Keywords.FOREACH)
{
var block = new ForeachBuilder(_reader, orderingBlock).Build();
orderingBlock.Children.Add(block);
}
else if (_reader.Current().Value == Keywords.DO)
{
var block = new DoWhileScopeBuilder(_reader, orderingBlock).Build();
orderingBlock.Children.Add(block);
}
else if (_reader.Current().Value == Keywords.WHILE)
{
var block = new WhileBlockBuilder(_reader, orderingBlock).Build();
orderingBlock.Children.Add(block);
}
else if (_reader.Current().Value == Keywords.TRY)
{
var block = new TryCatchFinallyBlockBuilder(_reader, orderingBlock).Build();
orderingBlock.Children.Add(block);
}
else
{
throwUnexceptedError();
}
break;
/*
* the operators that a expression can start with
* new;
* break;
* continue;
* throw;
* ++;
* --;
* new;
* var;
* identifier;
*
* function operator is not allowed ,it's just allowed in topiest block
*/
case TokenType.Operator:
switch (_reader.Current().OperatorType)
{
case OperatorType.Break:
orderingBlock.Children.Add(buildContinueOrBreakExpression(false));
throwIfBlockNotFinish();
return(orderingBlock);
case OperatorType.Continue:
orderingBlock.Children.Add(buildContinueOrBreakExpression(true));
throwIfBlockNotFinish();
return(orderingBlock);
case OperatorType.Declare:
var decExpression = new DeclareExpressionBuilder(_reader, orderingBlock).Build();
orderingBlock.Children.Add(decExpression);
break;
case OperatorType.Return:
orderingBlock.Children.Add(buildReturnExpression(orderingBlock));
throwIfBlockNotFinish();
return(orderingBlock);
//block finishd
case OperatorType.RightBrace:
return(orderingBlock);
case OperatorType.Increment:
case OperatorType.Decrement:
_reader.Back();
var expression0 = new ExpressionBuilder(_reader, true, orderingBlock).Build();
orderingBlock.Children.Add(expression0);
break;
default:
throwUnexceptedError();
break;
}
break;
case TokenType.Identifier:
_reader.Back();
var expression = new ExpressionBuilder(_reader, true, orderingBlock).Build();
orderingBlock.Children.Add(expression);
break;
case TokenType.String:
case TokenType.Number:
case TokenType.Bool:
case TokenType.Null:
default:
throwUnexceptedError();
break;
}
}
}
else
{
if (_reader.Current().OperatorType == OperatorType.Continue)
{
orderingBlock.Children.Add(buildContinueOrBreakExpression(true));
return(orderingBlock);
}
else if (_reader.Current().OperatorType == OperatorType.Break)
{
orderingBlock.Children.Add(buildContinueOrBreakExpression(false));
return(orderingBlock);
}
else if (_reader.Current().OperatorType == OperatorType.Return)
{
orderingBlock.Children.Add(buildReturnExpression(orderingBlock));
return(orderingBlock);
}
else
{
_reader.Back();
var expression = new ExpressionBuilder(_reader, true, orderingBlock).Build();
orderingBlock.Children.Add(expression);
return(orderingBlock);
}
}
throwError($"{_parentName} block is incompleted;");
return(orderingBlock);
}