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Difference between a View's Padding and Margin
...tom, right, and left sides.
An image says more than 1000 words (extracted from Margin Vs Padding - CSS Properties):
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Why does Apple recommend to use dispatch_once for implementing the singleton pattern under ARC?
... it's faster. It's also semantically cleaner, because it also protects you from multiple threads doing alloc init of your sharedInstance--if they all try at the same exact time. It won't allow two instances to be created. The entire idea of dispatch_once() is "perform something once and only once", ...
Cost of storing AMI
...icated" until the instance is launched, at which point a volume is created from the stored snapshots and you'll pay regular EBS volume fees and EBS snapshot billing.
S3-backed AMIs have their information stored in S3 and you will pay storage fees for the data being stored in S3 according to the S3 p...
PHP: Storing 'objects' inside the $_SESSION
... whole cloth based on data stashed in hidden form fields, or re-query them from the DB each time, you are using state. HTTP is stateless (more or less; but see GET vs. PUT) but almost everything anybody cares to do with a web app requires state to be maintained somewhere. Acting as if pushing the ...
What does rake db:test:prepare actually do?
... updates db/schema.rb. The rake
db:test:load recreates the test database from the current
db/schema.rb. On subsequent attempts, it is a good idea to first run
db:test:prepare, as it first checks for pending migrations and warns
you appropriately.
-- http://guides.rubyonrails.org/testing.ht...
How to convert an int value to string in Go?
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@luke it comes from the C heritage where the entire machine might have 256K memory; usability was sacrificed to fit more functionality in. The creators of Go are all deeply embedded in that heritage and feel entirely comfortable with these...
How can I check if a Perl array contains a particular value?
...irst and then check the hash. If memory is a concern, then move each item from the array into the hash. More memory efficient but destroys the original array.
If same values are searched repeatedly within the array, lazily build a cache. (as each item is searched, first check if the search result ...
Using :after to clear floating elements
...er support. :: is the newer format indented to distinguish pseudo content from pseudo selectors. If you don't need IE 8 support, feel free to use the double-colon. css-tricks.com/almanac/selectors/a/after-and-before
– retroriff
Dec 7 '16 at 7:15
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Angularjs Template Default Value if Binding Null / Undefined (With Filter)
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This is more intuitive, especially when coming from a programming background. Ternary operators pave way for simple If else Ifs.
– asgs
Jul 29 '15 at 18:42
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Laravel migration: unique key is too long, even if specified
...or storing "emojis" in the database. If you are upgrading your application from Laravel 5.3, you are not required to switch to this character set.
Update 2
Current production MariaDB versions DO NOT support this setting by default globally. It is implemented in MariaDB 10.2.2+ by default.
Soluti...