/// <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(LinqUnionExpression expression)
{
var firstSource = this.GenerateCode(expression.FirstSource);
var secondSource = this.GenerateCode(expression.SecondSource);
return(firstSource.Call("Union", secondSource));
}
/// <summary>
/// Evalutes the specified expression
/// </summary>
/// <param name="expression">The expression to evaluate.</param>
/// <returns>Value of the expression</returns>
public QueryValue Visit(LinqUnionExpression expression)
{
var firstSource = this.EvaluateCollection(expression.FirstSource);
var secondSource = this.EvaluateCollection(expression.SecondSource);
return(firstSource.Union(secondSource));
}
/// <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(LinqUnionExpression expression)
{
var firstSource = this.ReplaceExpression(expression.FirstSource);
var secondSource = this.ReplaceExpression(expression.SecondSource);
if (HasChanged(expression.FirstSource, firstSource) ||
HasChanged(expression.SecondSource, secondSource))
{
return(new LinqUnionExpression(firstSource, secondSource, expression.ExpressionType));
}
return(expression);
}
/// <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(LinqUnionExpression expression)
{
var firstSource = this.ResolveTypes(expression.FirstSource);
var secondSource = this.ResolveTypes(expression.SecondSource);
var firstSourceType = ValidateSourceIsACollection(firstSource);
var secondSourceType = ValidateSourceIsACollection(secondSource);
// For now, only add support for primitive types
ExceptionUtilities.Assert(
((IQueryClrType)firstSourceType.ElementType).ClrType.Equals(((IQueryClrType)secondSourceType.ElementType).ClrType),
"Expecting same types in both collections.");
return(new LinqUnionExpression(firstSource, secondSource, firstSourceType));
}
/// <summary>
/// Visits a QueryExpression tree whose root node is the LinqUnionExpression.
/// </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(LinqUnionExpression expression)
{
throw new TaupoNotSupportedException("Not supported");
}
