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Django - How to rename a model field using South?
...going to use this, make sure "app_foo" is the database table name, so for example: "mainapp_profile", "name" is the old column name of the database (not the model field name), for example: "user_id" and "full_name" would be the new name you want the column to have (again, database column and not fie...
How to test code dependent on environment variables using JUnit?
...le() {
String value = withEnvironmentVariable("name", "value")
.execute(() -> System.getenv("name"));
assertEquals("value", value);
}
}
For Java 5 to 7 the library System Rules has a JUnit rule called EnvironmentVariables.
import org.junit.contrib.java.lang.system.EnvironmentVari...
Why is there a `null` value in JavaScript?
In JavaScript, there are two values which basically say 'I don't exist' - undefined and null .
12 Answers
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Visual Studio 64 bit?
...
For numerous reasons, No.
Why is explained in this MSDN post.
First, from a performance perspective the pointers get larger, so data
structures get larger, and the processor cache stays the same size.
That basically results in a raw speed hit (your mileage m...
How to properly seed random number generator
... for all pseudo-random libraries, you have to set the seed only once, for example when initializing your program unless you specifically need to reproduce a given sequence (which is usually only done for debugging and unit testing).
After that you simply call Intn to get the next random integer.
M...
How do I list loaded plugins in Vim?
...imilar Vim commands, is that they display information in a large slab of text, which is very hard to visually parse.
To get around this, I wrote Headlights, a plugin that adds a menu to Vim showing all loaded plugins, TextMate style. The added benefit is that it shows plugin commands, mappings, fil...
Salting Your Password: Best Practices?
... been curious... Which is better when salting a password for hashing: prefix, or postfix? Why? Or does it matter, so long as you salt?
...
jQuery: Difference between position() and offset()
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Whether they're the same depends on context.
position returns a {left: x, top: y} object relative to the offset parent
offset returns a {left: x, top: y} object relative to the document.
Obviously, if the document is the offset parent, which is often the case,...
Is there a “null coalescing” operator in JavaScript?
...{
return arguments[i];
}
}
return null;
}
var xyz = {};
xyz.val = coalesce(null, undefined, xyz.val, 5);
// xyz.val now contains 5
this solution works like the SQL coalesce function, it accepts any number of arguments, and returns null if none of them have a value. I...
Convert a string to int using sql query
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How do I catch/prevent the exception when one of the fields is non-numeric? I would have expected it to convert to 0.
– Chloe
Jun 13 '13 at 17:47
...