Expression ParseExpression(Precedence p, bool vectorMode)
{
var e = ParseUnaryExpression(vectorMode);
while (e != null)
{
var op = Peek();
if (op == TokenType.Period)
{
Consume();
var id = Consume();
if (!IsIdentifier(id))
{
Error("Expected identifier after '.'");
}
e = new MemberExpression(e, id.Value);
continue;
}
if (op == TokenType.LeftSquareBrace)
{
Consume();
var index = ParseExpression(Precedence.Invalid, true);
if (Peek() != TokenType.RightSquareBrace)
{
Error("Expected ]");
}
Consume();
e = new LookUpExpression(e, index);
continue;
}
if (p < Precedence.Assignment)
{
if (TryConsume(TokenType.Colon))
{
e = new NameValuePairExpression(e, Expect(ParseExpression(Precedence.Assignment, false)));
continue;
}
}
if (p < Precedence.Conditional)
{
if (TryConsume(TokenType.QuestionMark))
{
var case1 = Expect(ParseExpression(Precedence.Conditional, false));
if (!TryConsume(TokenType.Colon))
{
Error("Expected ':'");
}
var case2 = Expect(ParseExpression(Precedence.Conditional, false));
e = new ConditionalExpression(e, case1, case2);
continue;
}
}
if (p < Precedence.Multiplicative)
{
if (TryConsume(TokenType.Mul))
{
e = new MultiplyExpression(e, Expect(ParseExpression(Precedence.Multiplicative, false)));
continue;
}
if (TryConsume(TokenType.Div))
{
e = new DivideExpression(e, Expect(ParseExpression(Precedence.Multiplicative, false)));
continue;
}
}
if (p < Precedence.Additive)
{
if (TryConsume(TokenType.Plus))
{
e = new AddExpression(e, Expect(ParseExpression(Precedence.Additive, false)));
continue;
}
if (TryConsume(TokenType.Minus))
{
e = new SubtractExpression(e, Expect(ParseExpression(Precedence.Additive, false)));
continue;
}
}
if (p < Precedence.LogicalAnd)
{
if (TryConsume(TokenType.LogAnd))
{
e = new LogicalAndExpression(e, Expect(ParseExpression(Precedence.LogicalAnd, false)));
continue;
}
}
if (p < Precedence.LogicalOr)
{
if (TryConsume(TokenType.LogOr))
{
e = new LogicalOrExpression(e, Expect(ParseExpression(Precedence.LogicalOr, false)));
continue;
}
}
if (p < Precedence.Relational)
{
if (TryConsume(TokenType.LessThan))
{
e = new LessThanExpression(e, Expect(ParseExpression(Precedence.Relational, false)));
continue;
}
if (TryConsume(TokenType.LessOrEqual))
{
e = new LessOrEqualExpression(e, Expect(ParseExpression(Precedence.Relational, false)));
continue;
}
if (TryConsume(TokenType.GreaterThan))
{
e = new GreaterThanExpression(e, Expect(ParseExpression(Precedence.Relational, false)));
continue;
}
if (TryConsume(TokenType.GreaterOrEqual))
{
e = new GreaterOrEqualExpression(e, Expect(ParseExpression(Precedence.Relational, false)));
continue;
}
if (TryConsume(TokenType.NotEqual))
{
e = new NotEqualExpression(e, Expect(ParseExpression(Precedence.Relational, false)));
continue;
}
if (TryConsume(TokenType.Equal))
{
e = new EqualExpression(e, Expect(ParseExpression(Precedence.Relational, false)));
continue;
}
}
if (p < Precedence.NullCoalescing)
{
if (TryConsume(TokenType.DoubleQuestionMark))
{
e = new NullCoalesceExpression(e, Expect(ParseExpression(Precedence.NullCoalescing, false)));
}
}
// Vector op
if (vectorMode && p == Precedence.Invalid && Peek() == TokenType.Comma)
{
var comps = new List <Expression>();
comps.Add(e);
while (TryConsume(TokenType.Comma))
{
e = Expect(ParseExpression(Precedence.Invalid, false));
comps.Add(e);
}
e = new VectorExpression(comps.ToArray()).TryFold();
}
break;
}
return(e);
}