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Null vs. False vs. 0 in PHP
...mpatibility). Despite the design wishing some consistency (outlined in the selected answer here), it all get confusing when you consider method returns that use false/null in not-so-easy to reason ways.
You will often see null being used when they are already using false for something. e.g. filter_i...
What makes Lisp macros so special?
...could write a macro that lets you say something like:
(setvar *rows* (sql select count(*)
from some-table
where column1 = "Yes"
and column2 like "some%string%")
And thats not even getting into Reader macros.
Hope this helps.
...
Differences between Oracle JDK and OpenJDK
...mostly based on HotSpot source code donated by Sun.
Moreover, OpenJDK was selected to be the reference implementation for Java 7 and is maintained by Oracle engineers.
There's a more detailed answer from 2012 on difference between JVM, JDK, JRE & OpenJDK, which links to an Oracle blog post:
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Why do we need message brokers like RabbitMQ over a database like PostgreSQL?
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PostgreSQL 9.5
PostgreSQL 9.5 incorporates SELECT ... FOR UPDATE ... SKIP LOCKED. This makes implementing working queuing systems a lot simpler and easier. You may no longer require an external queueing system since it's now simple to fetch 'n' rows that no other sess...
Spinlock versus Semaphore
...perly designed that way (probably a queue of pending operations, and here, selecting the next one, leaving the actual on the queue).
– Hibou57
Jul 30 '13 at 1:11
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GUI not working after rewriting to MVC
...he Model manages a single Piece, chosen at random. In response to a user's selection, the View invokes the check() method, while listening for a response from the Model via update(). The View then updates itself using information obtained from the Model. Similarly, the Controller may reset() the Mod...
Adaptive segue in storyboard Xcode 6. Is push deprecated?
... own custom code. When I download the sample project, it even shows to the selection of 'custom' on the segues in the storyboard file.
– Spencer Hall
Jun 24 '14 at 14:48
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How do I use WPF bindings with RelativeSource?
...bject that is also loaded from the database, but it only has access to the selected option. I had to explicitly set Path=DataContext.Message to get the binding to work. This makes sense, given that you can do relative bindings to width/height/etc. of a control.
– DrEsperanto
...
Is there a CSS selector by class prefix?
...ble with CSS2.1, but it is possible with CSS3 attribute substring-matching selectors (which are supported in IE7+):
div[class^="status-"], div[class*=" status-"]
Notice the space character in the second attribute selector. This picks up div elements whose class attribute meets either of these con...
How Do I 'git fetch' and 'git merge' from a Remote Tracking Branch (like 'git pull')
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Selecting just one branch: fetch/merge vs. pull
People often advise you to separate "fetching" from "merging". They say instead of this:
git pull remoteR branchB
do this:
git fetch remoteR
git merge remoteR b...