//> _let : _setVariable EQ _value
private bool _let()
{
TokenTry();
if (!_setVariable())
{
TokenBack();
return false;
}
if (!Accept(NakoTokenType.EQ))
{
TokenBack();
return false;
}
NakoNodeLet node = new NakoNodeLet();
node.VarNode = (NakoNodeVariable)lastNode; // _setVariable のノード
tok.MoveNext();
if (!_value())
{
throw new NakoParserException("代入文で値がありません。", tok.CurrentToken);
}
TokenFinally();
NakoNodeLetValue valuenode = new NakoNodeLetValue();
while (calcStack.Count > 0)
{
valuenode.AddChild(calcStack.Shift());
}
node.ValueNode = (NakoNode)valuenode;
parentNode.AddChild(node);
lastNode = node;
return true;
}
private bool _return()
{
TokenTry();
bool is_value = _value();
if (!Accept(NakoTokenType.RETURN))
{
TokenBack();
return false;
}
TokenFinally();
if(is_value){
NakoNodeLet node = new NakoNodeLet();
NakoNodeVariable sore = new NakoNodeVariable();
sore.varNo = (int)0;
sore.scope = NakoVariableScope.Global;
node.VarNode = sore;
NakoNodeLetValue valuenode = new NakoNodeLetValue();
while (calcStack.Count > 0)
{
valuenode.AddChild(calcStack.Shift());
}
node.ValueNode = (NakoNode)valuenode;
parentNode.AddChild(node);
}
parentNode.AddChild(new NakoNodeReturn());
tok.MoveNext();
return true;
}