/// <summary>
/// Resolves types for the specified expression.
/// </summary>
/// <param name="expression">The expression to resolve types for.</param>
/// <returns>Expression with resolved types.</returns>
public QueryExpression Visit(LinqFirstOrDefaultExpression expression)
{
var source = this.ResolveTypes(expression.Source);
var sourceType = ValidateSourceIsACollection(source);
var lambda = expression.Lambda != null?this.ResolveLambdaTypes(expression.Lambda, sourceType) : null;
return(new LinqFirstOrDefaultExpression(source, lambda, sourceType.ElementType));
}
/// <summary>
/// Visits a QueryExpression tree whose root node is the LinqFirstOrDefaultExpression.
/// </summary>
/// <param name="expression">The root node of the expression tree being visited.</param>
/// <returns>Uri query string representing the expression.</returns>
public virtual string Visit(LinqFirstOrDefaultExpression expression)
{
throw new TaupoNotSupportedException("Not supported");
}
/// <summary>
/// Generates System.CodeDom.CodeExpression from the given expression.
/// </summary>
/// <param name="expression">Expression from which System.CodeDom.CodeExpression is generated.</param>
/// <returns>Generated System.CodeDom.CodeExpression.</returns>
public virtual CodeExpression Visit(LinqFirstOrDefaultExpression expression)
{
return(this.VisitQueryMethodWithLambdaExpression(expression, "FirstOrDefault"));
}
/// <summary>
/// Evaluates the specified expression.
/// </summary>
/// <param name="expression">The expression to evaluate.</param>
/// <returns>Value of the expression.</returns>
public virtual QueryValue Visit(LinqFirstOrDefaultExpression expression)
{
return(this.VisitFirstExpression(expression, true));
}
/// <summary>
/// Replaces the given expression.
/// </summary>
/// <param name="expression">The root node of the expression tree being visited.</param>
/// <returns>Replaced expression.</returns>
public virtual QueryExpression Visit(LinqFirstOrDefaultExpression expression)
{
return(this.VisitQueryMethodWithLambdaExpression(expression, (s, l, t) => new LinqFirstOrDefaultExpression(s, l, t)));
}
