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How can I convert a string to a number in Perl?
I have a string which holds a decimal value in it and I need to convert that string into a floating point variable. So an example of the string I have is "5.45" and I want a floating point equivalent so I can add .1 to it. I have searched around the internet, but I only see how to convert a string t...
Vagrant's port forwarding not working [closed]
... of just more comments.
First thing: try curl 'http://localhost:80' from within the VM. If that doesn't work, then it's definitely not the port forwarding.
Next: try curl -v 'http://localhost:4567/' from your host machine. Curl might give you a better error message than Safari.
I'd check that t...
Immutability of Strings in Java
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str is not an object, it's a reference to an object. "Hello" and "Help!" are two distinct String objects. Thus, str points to a string. You can change what it points to, but not that which it points at.
Take this code, for example:
String s1 = "He...
What is PECS (Producer Extends Consumer Super)?
...dr: "PECS" is from the collection's point of view. If you are only pulling items from a generic collection, it is a producer and you should use extends; if you are only stuffing items in, it is a consumer and you should use super. If you do both with the same collection, you shouldn't use either ext...
What is the __del__ method, How to call it?
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__del__ is a finalizer. It is called when an object is garbage collected which happens at some point after all references to the object have been deleted.
In a simple case this could be right after you say del x or, if x is a local variable, after...
How do I create a self-signed certificate for code signing on Windows?
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If you're using an older version such as Windows 7, you'll need to stick with MakeCert or another solution. Some people suggest the Public Key Infrastructure Powershell (PSPKI) Module.
Original Answer
While you can create a self-signed code-signing certificate (SPC - Software Publisher Certificat...
HTML5 LocalStorage: Checking if a key exists [duplicate]
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Quoting from the specification:
The getItem(key) method must return the current value associated with the given key. If the given key does not exist in the list associated with the object then this method must return null.
You should actually check against null....
Does using final for variables in Java improve garbage collection?
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Here's a slightly different example, one with final reference-type fields rather than final value-type local variables:
public class MyClass {
public final MyOtherObject obj;
}
Every time you create an instance of MyClass, you'll be creating an outgoing refer...
How is Docker different from a virtual machine?
...to try to understand the difference between Docker and a full VM. How does it manage to provide a full filesystem, isolated networking environment, etc. without being as heavy?
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How can I force browsers to print background images in CSS?
...irectly in the page because there are several of them being used as CSS sprites.)
12 Answers
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