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Why do pthreads’ condition variable functions require a mutex?
...adcast to, one or more of the threads on the waiting list will be woken up and the mutex will be magically locked again for that thread.
You typically see the following operation with condition variables, illustrating how they work. The following example is a worker thread which is given work via a...
library not found for -lPods
...tion to your project, Xcode knows about the project in the Pods/ directory and how to build libPods.a.
– Jonathan Tran
Jul 8 '13 at 0:59
13
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How to validate an email address in PHP
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The easiest and safest way to check whether an email address is well-formed is to use the filter_var() function:
if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
// invalid emailaddress
}
Additionally you can check whether the do...
How to map and remove nil values in Ruby
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Ruby 2.7 is introducing filter_map for this exact purpose. It's idiomatic and performant, and I'd expect it to become the norm very soon.
For example:
numbers = [1, 2, 5, 8, 10, 13]
enum.filter_map { |i| i * 2 if i.even? }
# => [4, 16, 20]
In your case, as the block evaluates to falsey, simp...
How to replace a string in multiple files in linux command line
....bak 's/foo/bar/g' *.xx moves all .xx files to the equivalent .xx.bak name and then generates the .xx files with the foo→bar substitution.
– Anaphory
Oct 4 '14 at 22:35
26
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Django Template Variables and Javascript
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10 years later and Django has introduced a built in template filter just for this: docs.djangoproject.com/en/2.1/ref/templates/builtins/…
– Jon Sakas
Jan 19 '19 at 19:55
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Why doesn't Objective-C support private methods?
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The answer is... well... simple. Simplicity and consistency, in fact.
Objective-C is purely dynamic at the moment of method dispatch. In particular, every method dispatch goes through the exact same dynamic method resolution point as every other method dispatch. At...
Responsive font size in CSS
... respond to the browser zoom/type size settings, such as if you press Ctrl and + together on the keyboard while in the browser.
Media Queries
You would have to look at using media queries to reduce the font-size at certain intervals where it starts breaking your design and creating scrollbars.
For e...
Why can templates only be implemented in the header file?
Quote from The C++ standard library: a tutorial and handbook :
17 Answers
17
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Using CSS :before and :after pseudo-elements with inline CSS?
... an HTML email signature with inline CSS (i.e. CSS in style attributes), and I am curious as to whether it's possible to use the :before and :after pseudo-elements.
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