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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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How do I create a comma-separated list from an array in PHP?
...me. For example, maybe you want to quote each fruit and then separate them all by commas:
$prefix = $fruitList = '';
foreach ($fruits as $fruit)
{
$fruitList .= $prefix . '"' . $fruit . '"';
$prefix = ', ';
}
Also, if you just do it the "normal" way of appending a comma after each item (l...
Real world use of JMS/message queues? [closed]
...MS (ActiveMQ is a JMS broker implementation) can be used as a mechanism to allow asynchronous request processing. You may wish to do this because the request take a long time to complete or because several parties may be interested in the actual request. Another reason for using it is to allow mul...
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...
SVN: Is there a way to mark a file as “do not commit”?
...rtoiseSVN has a built in changelist, "ignore-on-commit", which is automatically excluded from commits. The command-line client does not have this, so you need to use multiple changelists to accomplish this same behavior (with caveats):
one for work you want to commit [work]
one for things you want...
Why is creating a Thread said to be expensive?
... there is a fair bit of work involved:
A large block of memory has to be allocated and initialized for the thread stack.
System calls need to be made to create / register the native thread with the host OS.
Descriptors need to be created, initialized and added to JVM-internal data structures.
It...
How to $http Synchronous call with AngularJS
Is there any way to make a synchronous call with AngularJS?
7 Answers
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