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Linux: copy and create destination dir if it does not exist
...nd (or probably an option to cp) that creates the destination directory if it does not exist.
21 Answers
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Shall we always use [unowned self] inside closure in Swift
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No, there are definitely times where you would not want to use [unowned self]. Sometimes you want the closure to capture self in order to make sure that it is still around by the time the closure is called.
Example: Making an asynchronous netw...
Is it secure to store passwords as environment variables (rather than as plain text) in config files
I work on a few apps in rails, django (and a little bit of php), and one of the things that I started doing in some of them is storing database and other passwords as environment variables rather than plain text in certain config files (or in settings.py, for django apps).
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What is the difference between == and equals() in Java?
...r to your question is "yes", but...
.equals(...) will only compare what it is written to compare, no more, no less.
If a class does not override the equals method, then it defaults to the equals(Object o) method of the closest parent class that has overridden this method.
If no parent classes ha...
Performance differences between debug and release builds
I must admit, that usually I haven't bothered switching between the Debug and Release configurations in my program, and I have usually opted to go for the Debug configuration, even when the programs are actually deployed at the customers place.
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How can I export tables to Excel from a webpage [closed]
...in. You get a grid that sorts, filters, orders, and pages your data, and with just a few extra lines of code and two small files included, you get export to Excel, PDF, CSV, to clipboard and to the printer.
This is all the code that's required:
$(document).ready( function () {
$('#example')...
ALTER TABLE without locking the table?
...ySQL, the whole table is read-locked (allowing concurrent reads, but prohibiting concurrent writes) for the duration of the statement. If it's a big table, INSERT or UPDATE statements could be blocked for a looooong time. Is there a way to do a "hot alter", like adding a column in such a way that th...
SQL JOIN - WHERE clause vs. ON clause
After reading it, this is not a duplicate of Explicit vs Implicit SQL Joins .
The answer may be related (or even the same) but the question is different.
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Can two applications listen to the same port?
...lications on the same machine bind to the same port and IP address? Taking it a step further, can one app listen to requests coming from a certain IP and the other to another remote IP?
I know I can have one application that starts off two threads (or forks) to have similar behavior, but can two ap...
window.onload vs
...d the onload event of the body tag? when do I use which and how should it be done correctly?
13 Answers
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