/// <summary>
/// Converts the <see cref="QueryValue"/> to a particular <see cref="QueryType"/>.
/// </summary>
/// <param name="type">The type for the As operation.</param>
/// <returns>The <see cref="QueryValue"/> converted to the specified type if successful. Returns null if this operation fails.</returns>
public override QueryValue TreatAs(QueryType type)
{
return(this.EvaluationStrategy.Cast(this, type as QueryScalarType));
}
/// <summary>
/// Converts the <see cref="QueryValue"/> to a particular <see cref="QueryType"/>.
/// </summary>
/// <param name="type">The type for the As operation.</param>
/// <returns>The <see cref="QueryValue"/> converted to the specified type if successful. Returns null if this operation fails.</returns>
public override QueryValue TreatAs(QueryType type)
{
return(type.CreateErrorValue(new QueryError("Cannot perform TreatAs on a record value")));
}
/// <summary>
/// Initializes a new instance of the QueryCollectionType class.
/// </summary>
/// <param name="elementType">Type of a single element in the collection.</param>
/// <param name="evaluationStrategy">The evaluation strategy.</param>
protected QueryCollectionType(QueryType elementType, IQueryEvaluationStrategy evaluationStrategy)
: base(evaluationStrategy)
{
this.ElementType = elementType;
}
/// <summary>
/// Determines whether the type can be assigned from another.
/// </summary>
/// <param name="queryType">Type to assign from.</param>
/// <returns>True if assignment is possible, false otherwise.</returns>
public virtual bool IsAssignableFrom(QueryType queryType)
{
return(object.ReferenceEquals(this, queryType));
}
/// <summary>
/// Checks if a <see cref="QueryValue"/> is of a particular <see cref="QueryType"/>. This operation will return a true if the value is of the specified type.
/// </summary>
/// <param name="type">The type for the IsOf operation.</param>
/// <param name="performExactMatch">Determines if an exact match needs to be performed.</param>
/// <returns>A <see cref="QueryValue"/> containing true or false depending on whether the value is of the specified type or not.</returns>
public override QueryValue IsOf(QueryType type, bool performExactMatch)
{
return(type.CreateErrorValue(new QueryError("Cannot perform IsOf on a record value")));
}
/// <summary>
/// Evaluates member method of a spatial instance.
/// </summary>
/// <param name="instance">The instance of query value object</param>
/// <param name="resultType">The function result type.</param>
/// <param name="methodName">The member method to evaluate.</param>
/// <param name="arguments">Arguments for the function call.</param>
/// <returns>Query value which is the result of function evaluation.</returns>
public QueryValue EvaluateMemberMethod(QueryValue instance, QueryType resultType, string methodName, params QueryValue[] arguments)
{
throw new TaupoNotSupportedException("Attempt to use evaluation strategy from " + typeof(QueryUnresolvedType).Name + ". Please resolve expression first.");
}
/// <summary>
/// Evaluates member property of a spatial instance.
/// </summary>
/// <param name="instance">The instance of query value object</param>
/// <param name="resultType">The proeprty result type.</param>
/// <param name="memberPropertyName">The member property name to evaluate.</param>
/// <returns>Query value which is the result of method evaluation.</returns>
public QueryValue EvaluateMemberProperty(QueryValue instance, QueryType resultType, string memberPropertyName)
{
throw new TaupoNotSupportedException("Attempt to use evaluation strategy from " + typeof(QueryUnresolvedType).Name + ". Please resolve expression first.");
}
/// <summary>
/// Evaluates function import.
/// </summary>
/// <param name="resultType">The function import result type.</param>
/// <param name="functionImport">The function import to evaluate.</param>
/// <param name="arguments">The arguments for the function import call.</param>
/// <returns>Query value which is the result of function import evaluation.</returns>
public QueryValue EvaluateFunctionImport(QueryType resultType, FunctionImport functionImport, params QueryValue[] arguments)
{
throw new TaupoNotSupportedException("Attempt to use evaluation strategy from " + typeof(QueryUnresolvedType).Name + ". Please resolve expression first.");
}
/// <summary>
/// Casts a <see cref="QueryValue"/> to a <see cref="QueryType"/>. The cast will return the value type cast to the new type.
/// </summary>
/// <param name="type">The type for the cast operation.</param>
/// <returns><see cref="QueryValue"/> which is cast to the appropriate type</returns>
public override QueryValue Cast(QueryType type)
{
return(type.CreateErrorValue(new QueryError("Cannot perform Cast on a reference value")));
}
/// <summary>
/// Initializes a new instance of the QueryExpression class.
/// </summary>
/// <param name="type">The type of expression.</param>
protected QueryExpression(QueryType type)
{
ExceptionUtilities.CheckArgumentNotNull(type, "type");
this.ExpressionType = type;
}
