ruby on rails - What is a better way to check for a nil object before calling a method on it? -

-

I have a call to this method that I want to use ... 

  financial_document .assets length

but financial_document.assets can be zero .

I could use ... 

  financial_document.assets.nil? ? '0': financial_document.assets.length

Is there a repetitive method to do this?

Personally, I use or operator / Keywords: 

  (financial_document.assets or []

By any means, say .length on an array Goes to 0 if zero .


Comments

Post a Comment

Popular posts from this blog

c++ - Linux and clipboard -

-
After selecting the copies of the buffer in Linux, after the text, we can click and paste the button between the mouse. I think there is a special buffer for this, I want to use it. Programming Language: C ++ Your Library: Qt Thanks. There is just one more correct answer than Paul Dixon, which answers your needs: / P > QClipboard * clipboard = QApplication :: clipboard (); CastString Selected Text = Clipboard-> Text (QClipboard :: Selection);
Read more

delphi - Mouseover hint for TChart series value -

-
I am using a TChart in Delphi 7, and I want to display charts sometime. I am using the following code to set the chain value to a database query: chart1.FreeAllSeries; Chart1.SeriesList.Clear; Chart1.AddSeries (TBarSeries.Create (self)); TBarSeries (chart1.Series [0]) BarStyle :. = BsRectGradient; Stop starting with Query 1; Executed; While EOF does not start chart1.Series [0]. Add (field 'flags' ('sum_actual_days'), Field Astrstring ('contract_no')); the upcoming; End; End; Each time (value) is now showing both the label below the bar and in a yellow rectangle above the bar. Rather than repeating the amount of label twice, I have some additional information from the query that I would like to show above the bar rather than the label (or, preferably, as a mouseover signal). Can it be done with TChart? And how ...? This can be done with a TChart using the onMouseMeave event of the chart. Something like this should start with you: Process TForm...
Read more

How to Create Master-Details view using Asp.Net MVC framework -

-
I am evaluating the Asp.Net MVC framework for my enterprise application for the past few weeks. The one thing I'm trying to achieve is the master-detail view. As it is very clear that there is no vivestate and there is no postback. For example, now I am using the product, customer, order and order details table from the Northwind database and I am using the especial MVC. I want to make master-detail view. Basically I do not have to have separate ideas (pages of other words) for order and order details. View order and order details should be included. How should I design my controller and see how to get this functionality. Thanks & amp; Regards, Burhanuddin Ghee You want to write a domain-specific view-model class Adds an order and details from its order (I'm assuming that order-> order details are 1-> n relation, not familiar with Northwind): public class command view model (Public order order); Set;} public inenemable & lt; Order deletate & gt; ...
Read more