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All Ruby tests raising: undefined method `authenticate' for nil:NilClass
...er! function is part of Rails 3 (using the new devise feature, of which I know little about). If the app can't find the User model (either because of namespace issues or whatever reason) then the method will fail. The "enki" application you linked to is now a Rails 3 application. It could be expe...
Check if an array is empty or exists
...ypeof array.length; // => "number"
Case Empty Array
Now since we tested all other possibilities, we're talking to an instance of Array. In order to make sure it's not empty, we ask about number of elements it's holding, and making sure it has more than zero elements.
firstArr...
Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
...is will throw a NullReferenceException in the second line and you want to know why .NET doesn't tell you that it was s that was null when the exception was thrown.
To understand why you don't get that piece of information you should remember that it is not C# source that executes but rather IL:
I...
Good or bad practice? Initializing objects in getter
...on of this issue is unnecessary as we will see shortly.
In general:
It's now time to look at lazy initialization in general:
Lazy initialization is usually used to delay the construction of objects that take a long time to be constructed or that take a lot of memory once fully constructed.
That is...
JavaScript equivalent of PHP's in_array()
...
There is now Array.prototype.includes:
The includes() method determines whether an array includes a certain
element, returning true or false as appropriate.
var a = [1, 2, 3];
a.includes(2); // true
a.includes(4); // false
...
What is the proper way to re-attach detached objects in Hibernate?
....getYetAnotherEntity(), you may have a LazyInit exception. The only way I know to overcome that is to use find. entity = em.find(entity.getClass(), entity.getId();
– John Rizzo
Mar 29 '11 at 9:16
...
How to save password when using Subversion from the console
...ew answer that's more up-to-date. (The store-passwords option in config is now deprecated, according to some default comments I found in my config file; it has been replaced by the same option in servers.)
– Kyle Strand
Sep 9 '14 at 23:24
...
How to fix org.hibernate.LazyInitializationException - could not initialize proxy - no Session
...of getCurrentSession() as one of the links you gave me suggested this, but now I'm affraid if it is wrong to do so
– Blerta Dhimitri
Feb 5 '14 at 11:39
2
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Is there a good charting library for iPhone? [closed]
I have a need to render and display charts (bar charts for now, but more types may be needed later) in an iPhone app I'm working on. I've done some looking around and it doesn't look like there are any really good, mature charting libraries for iPhone yet. I've also looked for something written for ...
open read and close a file in 1 line of code
Now I use:
11 Answers
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