internal static Expression SubExpr(ScriptLoadingContext lcontext, bool isPrimary)
{
Expression e = null;
Token T = lcontext.Lexer.Current;
if (T.IsUnaryOperator())
{
lcontext.Lexer.Next();
e = SubExpr(lcontext, false);
// check for power operator -- it be damned forever and ever for being higher priority than unary ops
Token unaryOp = T;
T = lcontext.Lexer.Current;
if (isPrimary && T.Type == TokenType.Op_Pwr)
{
List <Expression> powerChain = new List <Expression>();
powerChain.Add(e);
while (isPrimary && T.Type == TokenType.Op_Pwr)
{
lcontext.Lexer.Next();
powerChain.Add(SubExpr(lcontext, false));
T = lcontext.Lexer.Current;
}
e = powerChain[powerChain.Count - 1];
for (int i = powerChain.Count - 2; i >= 0; i--)
{
e = BinaryOperatorExpression.CreatePowerExpression(powerChain[i], e, lcontext);
}
}
e = new UnaryOperatorExpression(lcontext, e, unaryOp);
}
else
{
e = SimpleExp(lcontext);
}
T = lcontext.Lexer.Current;
if (isPrimary && T.IsBinaryOperator())
{
object chain = BinaryOperatorExpression.BeginOperatorChain();
BinaryOperatorExpression.AddExpressionToChain(chain, e);
while (T.IsBinaryOperator())
{
BinaryOperatorExpression.AddOperatorToChain(chain, T);
lcontext.Lexer.Next();
Expression right = SubExpr(lcontext, false);
BinaryOperatorExpression.AddExpressionToChain(chain, right);
T = lcontext.Lexer.Current;
}
e = BinaryOperatorExpression.CommitOperatorChain(chain, lcontext);
}
return(e);
}