/// <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(LinqTakeExpression expression)
{
CodeExpression source = this.GenerateCode(expression.Source);
CodeExpression skipCount = this.GenerateCode(expression.TakeCount);
return(source.Call("Take", skipCount));
}
/// <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(LinqTakeExpression expression)
{
var source = this.ResolveTypes(expression.Source);
var sourceType = ValidateSourceIsACollection(source);
var takeCount = this.ResolveTypes(expression.TakeCount);
return(new LinqTakeExpression(source, takeCount, sourceType));
}
/// <summary>
/// Evaluates the specified expression.
/// </summary>
/// <param name="expression">The expression to evaluate.</param>
/// <returns>Value of the expression.</returns>
public override QueryValue Visit(LinqTakeExpression expression)
{
return(this.VisitCollectionElementPrimitiveOrComplexTypeError(
expression,
delegate
{
return base.Visit(expression);
}));
}
/// <summary>
/// Visits a QueryExpression tree whose root node is the QueryTakeExpression.
/// </summary>
/// <param name="expression">The root node of the expression tree being visited.</param>
/// <returns>Uri query string representing the expression.</returns>
public override string Visit(LinqTakeExpression expression)
{
string source = this.ComputeUriInternal(expression.Source);
var takeCount = this.ExpressionConverter.Convert(expression.TakeCount);
this.SetTopQueryOption(takeCount);
this.hasQueryOption = true;
return(source);
}
/// <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(LinqTakeExpression expression)
{
QueryExpression source = this.ReplaceExpression(expression.Source);
QueryExpression takeCount = this.ReplaceExpression(expression.TakeCount);
if (HasChanged(expression.Source, source) || HasChanged(expression.TakeCount, takeCount))
{
return(new LinqTakeExpression(source, takeCount, expression.ExpressionType));
}
return(expression);
}
/// <summary>
/// Evaluates the specified expression.
/// </summary>
/// <param name="expression">The expression to evaluate.</param>
/// <returns>Value of the expression.</returns>
public virtual QueryValue Visit(LinqTakeExpression expression)
{
var source = this.EvaluateCollection(expression.Source);
var takeCount = this.Evaluate(expression.TakeCount) as QueryScalarValue;
if (takeCount == null)
{
throw new TaupoInvalidOperationException("Take count expression must be a primitive.");
}
return(source.Take(takeCount));
}
/// <summary>
/// Filters the specified expression. Skip top expression.
/// </summary>
/// <param name="expression">The expression to filter.</param>
/// <returns>The filtered expression</returns>
public override QueryExpression Visit(LinqTakeExpression expression)
{
return(expression.Source.Accept(this));
}
/// <summary>
/// Visits a QueryExpression tree whose root node is the QueryTakeExpression.
/// </summary>
/// <param name="expression">The root node of the expression tree being visited.</param>
/// <returns>Uri query string representing the expression.</returns>
public override string Visit(LinqTakeExpression expression)
{
string source = this.ComputeUriInternal(expression.Source);
var takeCount = this.ExpressionConverter.Convert(expression.TakeCount);
this.SetTopQueryOption(takeCount);
this.hasQueryOption = true;
return source;
}
/// <summary>
/// Visits a QueryExpression tree whose root node is the LinqTakeExpression.
/// </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(LinqTakeExpression expression)
{
throw new TaupoNotSupportedException("Not supported");
}
