public void Aggregate <TSource, TResult>(string aggregateName, IEnumerable <KeyValuePair <string, LambdaExpression> > expressions, Type customFactoryType)
{
var previousBuildAction = _buildAction;
_buildAction = name =>
{
var patternBuilder = new PatternBuilder(typeof(TResult), name);
BuildResult result;
using (_symbolStack.Frame())
{
var aggregateBuilder = patternBuilder.Aggregate();
var previousResult = previousBuildAction(null);
var sourceBuilder = previousResult.Pattern;
var rewrittenExpressionCollection = new List <KeyValuePair <string, LambdaExpression> >();
foreach (var item in expressions)
{
var expression = sourceBuilder.DslPatternExpression(_symbolStack.Scope.Declarations, item.Value);
rewrittenExpressionCollection.Add(new KeyValuePair <string, LambdaExpression>(item.Key, expression));
}
aggregateBuilder.Aggregator(aggregateName, rewrittenExpressionCollection, customFactoryType);
aggregateBuilder.Pattern(sourceBuilder);
result = new BuildResult(patternBuilder, aggregateBuilder, sourceBuilder);
}
_symbolStack.Scope.Add(patternBuilder.Declaration);
return(result);
};
}
public void GroupBy <TSource, TKey, TElement>(Expression <Func <TSource, TKey> > keySelector, Expression <Func <TSource, TElement> > elementSelector)
{
var previousBuildAction = _buildAction;
_buildAction = name =>
{
var patternBuilder = new PatternBuilder(typeof(IGrouping <TKey, TElement>), name);
BuildResult result;
using (_symbolStack.Frame())
{
var aggregateBuilder = patternBuilder.Aggregate();
var previousResult = previousBuildAction(null);
var sourceBuilder = previousResult.Pattern;
var keySelectorExpression = sourceBuilder.DslPatternExpression(_symbolStack.Scope.Declarations, keySelector);
var elementSelectorExpression = sourceBuilder.DslPatternExpression(_symbolStack.Scope.Declarations, elementSelector);
aggregateBuilder.GroupBy(keySelectorExpression, elementSelectorExpression);
aggregateBuilder.Pattern(sourceBuilder);
result = new BuildResult(patternBuilder, aggregateBuilder, sourceBuilder);
}
_symbolStack.Scope.Add(patternBuilder.Declaration);
return(result);
};
}
private IRuleDefinition BuildMultipleOrdersRule()
{
//rule "Multiple Orders Rule"
//when
// customer = Customer(x => x.IsPreferred);
// orders = Query(
// Order(x => x.Customer == customer, x => x.IsOpen)
// Collect()
// Where(c => c.Count() >= 3)
// );
//then
// Console.WriteLine("Customer {0} has {1} open order(s)", customer.Name, orders.Count());
var builder = new RuleModel.Builders.RuleBuilder();
builder.Name("Multiple Orders Rule");
PatternBuilder customerPattern = builder.LeftHandSide().Pattern(typeof(Customer), "customer");
Expression <Func <Customer, bool> > customerCondition = customer => customer.IsPreferred;
customerPattern.Condition(customerCondition);
PatternBuilder ordersPattern = builder.LeftHandSide().Pattern(typeof(IEnumerable <Order>), "orders");
Expression <Func <IEnumerable <Order>, bool> > aggregateCondition = orders => orders.Count() >= 3;
ordersPattern.Condition(aggregateCondition);
var aggregate = ordersPattern.Aggregate();
aggregate.Collect();
var orderPattern = aggregate.Pattern(typeof(Order), "order");
Expression <Func <Order, Customer, bool> > orderCondition1 = (order, customer) => order.Customer == customer;
orderPattern.Condition(orderCondition1);
Expression <Func <Order, bool> > orderCondition2 = order => order.IsOpen;
orderPattern.Condition(orderCondition2);
Expression <Action <IContext, Customer, IEnumerable <Order> > > action =
(ctx, customer, orders) => Console.WriteLine("Customer {0} has {1} open order(s)", customer.Name, orders.Count());
builder.RightHandSide().Action(action);
return(builder.Build());
}
public void SelectMany <TSource, TResult>(Expression <Func <TSource, IEnumerable <TResult> > > selector)
{
var previousBuildAction = _buildAction;
_buildAction = name =>
{
var patternBuilder = new PatternBuilder(typeof(TResult), name);
BuildResult result;
using (_symbolStack.Frame())
{
var aggregateBuilder = patternBuilder.Aggregate();
var previousResult = previousBuildAction(null);
var sourceBuilder = previousResult.Pattern;
var selectorExpression = sourceBuilder.DslPatternExpression(_symbolStack.Scope.Declarations, selector);
aggregateBuilder.Flatten(selectorExpression);
aggregateBuilder.Pattern(sourceBuilder);
result = new BuildResult(patternBuilder, aggregateBuilder, sourceBuilder);
}
_symbolStack.Scope.Add(patternBuilder.Declaration);
return(result);
};
}
public void Collect <TSource>()
{
var previousBuildAction = _buildAction;
_buildAction = name =>
{
var patternBuilder = new PatternBuilder(typeof(IEnumerable <TSource>), name);
BuildResult result;
using (_symbolStack.Frame())
{
var aggregateBuilder = patternBuilder.Aggregate();
var previousResult = previousBuildAction(null);
var sourceBuilder = previousResult.Pattern;
aggregateBuilder.Collect();
aggregateBuilder.Pattern(sourceBuilder);
result = new BuildResult(patternBuilder, aggregateBuilder, sourceBuilder);
}
_symbolStack.Scope.Add(patternBuilder.Declaration);
return(result);
};
}