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Rails: How do I create a default value for attributes in Rails activerecord's model? [duplicate]
...tonymous: good point. I wonder if would also help to wrap the 'defaulting' block with a new_record? condition? (link)
– twelve17
Apr 30 '13 at 15:38
...
Does it make sense to use “as” instead of a cast even if there is no null check? [closed]
... fail, you should use as instead of a normal cast wrapped with a try-catch block. Moreover, use of as is recommended over a type check followed by a cast. Instead of:
if (x is SomeType)
((SomeType)x).SomeMethod();
which generates an isinst instruction for the is keyword, and a castclass instru...
How do I loop through or enumerate a JavaScript object?
...that JavaScript only has function scope. So what I actually meant was "if block".
– Andreas Grech
Nov 11 '11 at 11:08
1
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Is there a way to change the spacing between legend items in ggplot2?
...g5,g6,nrow=3) #see picture below, left
Notice that white squares begin blocking legend title (and eventually the graph itself if we kept increasing the value).
#This shows you why:
gt <- gp2 + theme(legend.key = element_rect(size = 10,color = 'yellow' ))
I haven't quite found a wor...
In laymans terms, what does 'static' mean in Java? [duplicate]
...unterTwo++; //Ok
}
}
Lastly, there are static initializers which are blocks of code that are run when the class is first loaded (which is usually just before a class is instantiated for the first time in an application) and (like static methods) cannot access non-static fields or methods.
pub...
What are the correct version numbers for C#?
... Major new features: generics, anonymous methods, nullable types, iterator blocks
C# 3.0 released with .NET 3.5 and VS2008 (November 2007). Major new features: lambda expressions, extension methods, expression trees, anonymous types, implicit typing (var), query expressions
C# 4.0 released with .NET...
Loading/Downloading image from URL on Swift
...ur application.
An easy way to make the same code run asynchronously, not blocking the UI, is by using GCD:
let url = URL(string: image.url)
DispatchQueue.global().async {
let data = try? Data(contentsOf: url!) //make sure your image in this url does exist, otherwise unwrap in a if let check ...
Useful example of a shutdown hook in Java?
...
(Optionally, .interrupt the working threads if they wait for data in some blocking call)
Wait for the working threads (executing writeBatch in your case) to finish, by calling the Thread.join() method on the working threads.
Terminate the program
Some sketchy code:
Add a static volatile boolean...
Why does HTML think “chucknorris” is a color?
... adamlevine does work as per jsfiddle.net/LdyZ8/2959 but the letters are blocked into ada00e000e which is padded to ada00e000e00 but then reduced down to the typical HEX 6 digit value of [ad]a0[0e]00[0e]00 thus making ad0e0e which appears in the jsfiddle above.
– Martin
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Update Row if it Exists Else Insert Logic with Entity Framework
...been bothering me for a while? Normally, I put my context in a short using block. Is it okay to leave the context in memory for a while? For example, during the life of a Windows form? I normally try and clean up database objects to ensure minimum load on the database. Is there no problem waiting to...