/// <summary>
/// Recognizes an addition or a subtraction.
/// </summary>
/// <returns>A <see cref="BinaryExpression"/></returns>
protected Expression Term()
{
Expression expr = Factor();
if (expr == null)
{
return(null);
}
var parts = new Queue <BinaryExpressionPart>();
while (TryMatchAny(TokenID.Plus, TokenID.Minus))
{
BinaryOperator oper = token.ToBinaryOperator();
Consume(1);
var factor = Required <Expression>(Factor, Resources.ExpressionRequired);
parts.Enqueue(new BinaryExpressionPart(oper, factor));
}
while (parts.Count > 0)
{
BinaryExpressionPart part = parts.Dequeue();
expr = new BinaryExpression(part.Operator, expr, part.Operand);
}
return(expr);
}
/// <summary>
/// Recognizes a multiplication, a divison, a modulo or a shift.
/// </summary>
/// <returns>A <see cref="BinaryExpression"/></returns>
protected Expression Factor()
{
Expression expr = Exponentiation();
if (expr == null)
{
return(null);
}
var parts = new Queue <BinaryExpressionPart>();
while (TryMatchAny(TokenID.Asterisk, TokenID.Slash, TokenID.Percent,
TokenID.DoubleLessThan, TokenID.DoubleGreaterThan))
{
BinaryOperator oper = token.ToBinaryOperator();
Consume(1);
var expon = Required <Expression>(Exponentiation, Resources.ExpressionRequired);
parts.Enqueue(new BinaryExpressionPart(oper, expon));
}
while (parts.Count > 0)
{
BinaryExpressionPart part = parts.Dequeue();
expr = new BinaryExpression(part.Operator, expr, part.Operand);
}
return(expr);
}
/// <summary>
/// Recognizes a logical expression.
/// </summary>
/// <returns>A <see cref="BinaryExpression"/></returns>
protected Expression Condition()
{
Expression expr = Relation();
if (expr == null)
{
return(null);
}
var parts = new Queue <BinaryExpressionPart>();
while (TryMatchAny(TokenID.Ampersand, TokenID.DoubleAmpersand,
TokenID.VerticalBar, TokenID.DoubleVerticalBar,
TokenID.Circumflex))
{
BinaryOperator oper = token.ToBinaryOperator();
Consume(1);
var relation = Required <Expression>(Relation, Resources.ExpressionRequired);
parts.Enqueue(new BinaryExpressionPart(oper, relation));
}
while (parts.Count > 0)
{
BinaryExpressionPart part = parts.Dequeue();
expr = new BinaryExpression(part.Operator, expr, part.Operand);
}
return(expr);
}