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An error occurred while installing pg (0.17.1), and Bundler cannot continue
I just installed Rails 4.0.2 and when creating a new app, in the bundle stage I get:
16 Answers
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What is a NullPointerException, and how do I fix it?
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When you declare a reference variable (i.e. an object) you are really creating a pointer to an object. Consider the following code where you declare a variable of primitive type int:
int x;
x = 10;
In this example, the variable x is an int and Java will initialize it to 0 for you. When yo...
glob exclude pattern
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Really interesting solution! But my case is going to be extremely slow to make a read twice. Also if the content of a folder is big on an network directory, is going to be slow again. But in any case, really handy.
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Auto code completion on Eclipse
I want Eclipse to automatically suggest to me all possible options, while I'm writing some variable/class name or keyword, like in Flash Develop or Visual Studio.
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Could not find method compile() for arguments Gradle
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Looking back all this time, this is the most likely problem I was having. I have since obviously far moved on, but after getting notifications that this question was still open I think its only proper to indicate this as the 'correct' ans...
nonlocal keyword in Python 2.x
...nswer by Elias Zamaria, but contrary to that answer does handle multiple calls of the outer function correctly. The "variable" inner.y is local to the current call of outer. Only it isn't a variable, since that is forbidden, but an object attribute (the object being the function inner itself). This...
Disable cache for some images
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Please note: You do not actually prevent the browser from caching the image, you only prevent looking at the cached image. Applying proper headers to your image is the best way imho (see the solution of lhunath below). Since this way you also fill the c...
Reserved keywords in JavaScript
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Here is my poem, which includes all of the reserved keywords in JavaScript, and is dedicated to those who remain honest in the moment, and not just try to score:
Let this long package float,
Goto private class if short.
While protected with debugger case,...
@UniqueConstraint annotation in Java
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@Entity
@Table(uniqueConstraints={@UniqueConstraint(columnNames = {"id_1" , "id_2"})})
public class class_name {
@Id
@GeneratedValue
public Long id;
@NotNull
public Long id_1;
@NotNull
public Long id_2;
}
Hope it helped.
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Is it pythonic to import inside functions?
...at it needs to import.
If I'm adding new code to an existing file I'll usually do the import where it's needed and then if the code stays I'll make things more permanent by moving the import line to the top of the file.
One other point, I prefer to get an ImportError exception before any code is r...