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The performance impact of using instanceof in Java
I am working on an application and one design approach involves extremely heavy use of the instanceof operator. While I know that OO design generally tries to avoid using instanceof , that is a different story and this question is purely related to performance. I was wondering if there is any per...
Static variables in JavaScript
...);
staticProperty is defined in the MyClass object (which is a function) and has nothing to do with its created instances, JavaScript treats functions as first-class objects, so being an object, you can assign properties to a function.
UPDATE: ES6 introduced the ability to declare classes through...
Request format is unrecognized for URL unexpectedly ending in
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i kept it as is and for now the error seems to have gone away. if i see the error again i'll move the webservices configs into the webserver section.
– Daniel Brink
Apr 20 '10 at 8:08
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Javascript infamous Loop issue? [duplicate]
...e first example:
JavaScript's scopes are function-level, not block-level, and creating a closure just means that the enclosing scope gets added to the lexical environment of the enclosed function.
After the loop terminates, the function-level variable i has the value 5, and that's what the inner fu...
SQL Server IN vs. EXISTS Performance
...t. The IN statement requires SQL Server to generate a complete result set, and then create a big IF statement I think.
– Randy Minder
Jan 14 '10 at 16:04
74
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How do I add a password to an OpenSSH private key that was generated without a password?
I generated an OpenSSH private key using puttygen (and exported it in OpenSSH format). How can I put a password on this existing key (I know how to generate a new key with a password)?
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How to get the Full file path from URI
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Use:
String path = yourAndroidURI.uri.getPath() // "/mnt/sdcard/FileName.mp3"
File file = new File(new URI(path));
or
String path = yourAndroidURI.uri.toString() // "file:///mnt/sdcard/FileName.mp3"
File file = new File(new URI(path));
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Do I set properties to nil in dealloc when using ARC?
...ment dealloc. However, if you have any non-object ivars that need special handling (e.g. allocated buffers that you need to free()) you still have to deal with those in dealloc.
Furthermore, if you've set yourself as the delegate of any objects, you should un-set that relationship in dealloc (this ...
How do you format an unsigned long long int using printf?
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Or to be precise it's for GNU libc, and doesn't work with Microsoft's C runtime.
– Mark Baker
Oct 8 '08 at 9:35
171
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Add a new column to existing table in a migration
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To create a migration, you may use the migrate:make command on the Artisan CLI. Use a specific name to avoid clashing with existing models
for Laravel 3:
php artisan migrate:make add_paid_to_users
for Laravel 5+:
php artisan make:migration add_paid_to_users_table --table=us...