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When should I use Lazy?
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You typically use it when you want to instantiate something the first time its actually used. This delays the cost of creating it till if/when it's needed instead of always incurring the cost.
Usually this is preferable when the obj...
Invalid date format specification in gemspec
...update --system
Edit: You can also try (as suggested by ZeissS)
gem install rubygems-update
update_rubygems
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What does it mean that Javascript is a prototype based language?
...instream] object-oriented languages to use prototypal inheritance. Almost all other object-oriented languages are classical.
In classical inheritance, the programmer writes a class, which defines an object. Multiple objects can be instantiated from the same class, so you have code in one place wh...
diff to output only the file names
..."29b". Use instead: rsync -ric --dry-run old/ new/ where the "-i" argument allows to obtain the file list directly via rsync -ric --dry-run old/ new/ | cut -d" " -f 2
– iolsmit
Mar 24 '15 at 17:15
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Why are primes important in cryptography?
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Most basic and general explanation: cryptography is all about number theory, and all integer numbers (except 0 and 1) are made up of primes, so you deal with primes a lot in number theory.
More specifically, some important cryptographic algorithms such as RSA critically depen...
C# LINQ find duplicates in List
...erable.GroupBy(x => x.Key).Any(g => g.Count() > 1);
Find out if all values in an enumerable are unique :
var allUnique = enumerable.GroupBy(x => x.Key).All(g => g.Count() == 1);
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CSS two divs next to each other
...d="narrow">Narrow (200px)</div>
</div>
This is basically just scraping the surface of flexbox. Flexbox can do pretty amazing things.
For older browser support, you can use CSS float and a width properties to solve it.
#narrow {
float: right;
width: 200px;
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Java synchronized method lock on object, or method?
... anyway. That's a bit misleading. Synchronizing on the method is functionally equivalent to having a synchronized (this) block around the body of the method. The object "this" doesn't become locked, rather the object "this" is used as the mutex and the body is prevented from executing concurrentl...
What is the meaning of symbol $ in jQuery?
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You know, this REALLY should be the right answer for this question... I can't believe all those joke-y answers got all the up-votes.
– reedvoid
Aug 15 '13 at 12:59
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What are the differences between JSON and JavaScript object? [duplicate]
...al notation, but there are differences between them.
For example, in JSON all keys must be quoted, while in object literals this is not necessary:
// JSON:
{ "foo": "bar" }
// Object literal:
var o = { foo: "bar" };
The quotes are mandatory on JSON because in JavaScript (more exactly in ECMAScr...