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Coalesce function for PHP?
...HP 7 introduced a real coalesce operator:
echo $_GET['doesNotExist'] ?? 'fallback'; // prints 'fallback'
If the value before the ?? does not exists or is null the value after the ?? is taken.
The improvement over the mentioned ?: operator is, that the ?? also handles undefined variables without...
Mediator Vs Observer Object-Oriented Design Patterns
...-to-many dependency between objects so that when one object changes state, all its dependents are notified and updated automatically.
The Mediator pattern:
Define an object that encapsulates how a set of objects interact. Mediator promotes loose coupling by keeping objects from referring to each o...
How to redirect to a 404 in Rails?
...ou want to show a 404 page, create a render_404 method (or not_found as I called it) in ApplicationController like this:
def not_found
raise ActionController::RoutingError.new('Not Found')
end
Rails also handles AbstractController::ActionNotFound, and ActiveRecord::RecordNotFound the same way....
Sphinx autodoc is not automatic enough
...for modules project.module1 and project.module2 will be generated automatically and placed into _autosummary directory.
PROJECT
=======
.. toctree::
.. autosummary::
:toctree: _autosummary
project.module1
project.module2
By default autosummary will generate only very short summaries fo...
How do synchronized static methods work in Java and can I use it for loading Hibernate entities?
If I have a util class with static methods that will call Hibernate functions to accomplish basic data access. I am wondering if making the method synchronized is the right approach to ensure thread-safety.
...
Bold & Non-Bold Text In A Single UILabel?
...deal with iOS5 old stuff besides syntax is shorter so everything becomes really simple:
Swift 5
func attributedString(from string: String, nonBoldRange: NSRange?) -> NSAttributedString {
let fontSize = UIFont.systemFontSize
let attrs = [
NSAttributedString.Key.font: UIFont.bold...
Is it possible to run a single test in MiniTest?
I can run all tests in a single file with:
13 Answers
13
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What is the best way to ensure only one instance of a Bash script is running? [duplicate]
...
If the script is the same across all users, you can use a lockfile approach. If you acquire the lock, proceed else show a message and exit.
As an example:
[Terminal #1] $ lockfile -r 0 /tmp/the.lock
[Terminal #1] $
[Terminal #2] $ lockfile -r 0 /tmp/the....
How can I get the concatenation of two lists in Python without modifying either one? [duplicate]
...
Actually you can do this by using the a non hidden function: import operator, operator.add(list1, list2)
– e-satis
Apr 13 '11 at 12:28
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How to check if a map contains a key in Go?
...ring) and ok will receive a bool that will be set to true if "foo" was actually present in the map
evaluates ok, which will be true if "foo" was in the map
If "foo" is indeed present in the map, the body of the if statement will be executed and val will be local to that scope.
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