/// <summary>
/// Evaluates the specified expression.
/// </summary>
/// <param name="expression">The expression to evaluate.</param>
/// <returns>Value of the expression.</returns>
public virtual QueryValue Visit(LinqSelectManyExpression expression)
{
var source = this.EvaluateCollection(expression.Source);
var collectionElementType = ((QueryCollectionType)expression.CollectionSelector.Body.ExpressionType).ElementType;
var collections = source.Elements.Select(v => new { Element = v, Collection = (QueryCollectionValue)this.EvaluateLambda <QueryValue>(expression.CollectionSelector, v) });
var flattenedStructure = new List <KeyValuePair <QueryValue, QueryValue> >();
foreach (var collectionStructure in collections)
{
foreach (var innerCollectionElement in collectionStructure.Collection.Elements)
{
flattenedStructure.Add(new KeyValuePair <QueryValue, QueryValue>(collectionStructure.Element, innerCollectionElement));
}
}
if (expression.ResultSelector != null)
{
var results = flattenedStructure.Select(v => this.EvaluateLambda <QueryValue>(expression.ResultSelector, v.Key, v.Value));
return(expression.ResultSelector.Body.ExpressionType.CreateCollectionType().CreateCollectionWithValues(results));
}
else
{
return(collectionElementType.CreateCollectionType().CreateCollectionWithValues(flattenedStructure.Select(s => s.Value)));
}
}
/// <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(LinqSelectManyExpression expression)
{
var source = this.ReplaceExpression(expression.Source);
var collectionSelector = (LinqLambdaExpression)this.ReplaceExpression(expression.CollectionSelector);
var resultSelector = expression.ResultSelector != null ? (LinqLambdaExpression)this.ReplaceExpression(expression.ResultSelector) : null;
if (HasChanged(expression.Source, source) || HasChanged(expression.CollectionSelector, collectionSelector) || HasChanged(expression.ResultSelector, resultSelector))
{
return(new LinqSelectManyExpression(source, collectionSelector, resultSelector, expression.ExpressionType));
}
else
{
return(expression);
}
}
/// <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 override CodeExpression Visit(LinqSelectManyExpression expression)
{
var source = this.GenerateCode(expression.Source);
var collectionSelector = this.GenerateCode(expression.CollectionSelector);
var resultSelector = expression.ResultSelector != null?this.GenerateCode(expression.ResultSelector) : null;
if (resultSelector != null)
{
return(source.Call("SelectMany", collectionSelector, resultSelector));
}
else
{
return(source.Call("SelectMany", collectionSelector));
}
}
/// <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(LinqSelectManyExpression expression)
{
var source = this.ResolveTypes(expression.Source);
var sourceType = ValidateSourceIsACollection(source);
var collectionSelector = this.ResolveLambdaTypes(expression.CollectionSelector, sourceType);
var elementCollectionType = ValidateSourceIsACollection(collectionSelector.Body);
if (expression.ResultSelector != null)
{
var resultSelector = this.ResolveLambdaTypes(expression.ResultSelector, sourceType, elementCollectionType);
return(new LinqSelectManyExpression(source, collectionSelector, resultSelector, resultSelector.Body.ExpressionType.CreateCollectionType()));
}
else
{
return(new LinqSelectManyExpression(source, collectionSelector, null, elementCollectionType));
}
}
/// <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 override CodeExpression Visit(LinqSelectManyExpression expression)
{
throw new TaupoNotSupportedException("Query syntax is not supported by Taupo at the moment.");
}
/// <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 override CodeExpression Visit(LinqSelectManyExpression expression)
{
var source = this.GenerateCode(expression.Source);
var collectionSelector = this.GenerateCode(expression.CollectionSelector);
var resultSelector = expression.ResultSelector != null ? this.GenerateCode(expression.ResultSelector) : null;
if (resultSelector != null)
{
return source.Call("SelectMany", collectionSelector, resultSelector);
}
else
{
return source.Call("SelectMany", collectionSelector);
}
}
/// <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 override CodeExpression Visit(LinqSelectManyExpression expression)
{
throw new TaupoNotSupportedException("Query syntax is not supported by Taupo at the moment.");
}
