public Expression Bind(PipelineExpression pipeline, EmbeddedPipelineBindingContext bindingContext, MethodCallExpression node, IEnumerable <Expression> arguments)
{
var source = new ZipExpression(
node.Type,
pipeline.Source,
arguments.First());
var lambda = ExpressionHelper.GetLambda(arguments.Last());
var input = new DocumentExpression(bindingContext.GetSerializer(typeof(object[]), null));
var itemA = new ArrayIndexExpression(
input,
Expression.Constant(0),
bindingContext.GetSerializer(lambda.Parameters[0].Type, source.Source));
var itemB = new ArrayIndexExpression(
input,
Expression.Constant(1),
bindingContext.GetSerializer(lambda.Parameters[1].Type, source.Other));
bindingContext.AddExpressionMapping(lambda.Parameters[0], itemA);
bindingContext.AddExpressionMapping(lambda.Parameters[1], itemB);
var selector = bindingContext.Bind(lambda.Body);
var serializer = bindingContext.GetSerializer(selector.Type, selector);
return(new PipelineExpression(
new SelectExpression(
source,
lambda.Parameters[0].Name + "_" + lambda.Parameters[1].Name,
selector),
new DocumentExpression(serializer)));
}
private BsonValue TranslateZip(ZipExpression node)
{
var inputs = new[] { TranslateValue(node.Source), TranslateValue(node.Other) };
return(new BsonDocument("$zip", new BsonDocument("inputs", new BsonArray(inputs))));
}
