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Why does typeof array with objects return “object” and not “array”? [duplicate]
Why is an array of objects considered an object, and not an array? For example:
4 Answers
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Why does this loop produce “warning: iteration 3u invokes undefined behavior” and output more than 4
...s no such thing as "unsigned integer overflow") means undefined behaviour. And this means anything can happen, and discussing why does it happen under the rules of C++ doesn't make sense.
C++11 draft N3337: §5.4:1
If during the evaluation of an expression, the result is not mathematically de...
Are (non-void) self-closing tags valid in HTML5?
...ich leads to <br /> meaning <br>> (i.e. <br>&gt;) and <title/hello/ meaning <title>hello</title>). This is an SGML rule that browsers did a very poor job of supporting, and the spec advises authors to avoid the syntax.
In XHTML, <foo /> means <foo>...
Shell script - remove first and last quote (") from a variable
...
There's a simpler and more efficient way, using the native shell prefix/suffix removal feature:
temp="${opt%\"}"
temp="${temp#\"}"
echo "$temp"
${opt%\"} will remove the suffix " (escaped with a backslash to prevent shell interpretation).
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Good reasons to prohibit inheritance in Java?
... Item 19 of Joshua Bloch's excellent book "Effective Java", called "Design and document for inheritance or else prohibit it". (It's item 17 in the second edition and item 15 in the first edition.) You should really read it, but I'll summarize.
The interaction of inherited classes with their parent...
When and why JPA entities should implement Serializable interface?
The question is in the title. Below I just described some of my thoughts and findings.
14 Answers
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Cannot read configuration file due to insufficient permissions
...s (Network Services, Local System, etc.), should have permission to access and read web.config file.
Update:
This updated answer is same as above, but a little longer and simpler and improved.
First of all: you don't have to change anything in your config file. It's OK. The problem is with window...
How can I merge two commits into one if I already started rebase?
...base todo list, that is into a commit on a previous line. Changing the command on your todo list’s very first line to squash will always produce this error as there is nothing for the first commit to squash into.
The Fix
First get back to where you started with
$ git rebase --abort
Say your h...
When do I need to use AtomicBoolean in Java?
How I can use AtomicBoolean and what is that class for?
5 Answers
5
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Checking if an Android application is running in the background
... completely reliable:
The right solution (credits go to Dan, CommonsWare and NeTeInStEiN)
Track visibility of your application by yourself using Activity.onPause, Activity.onResume methods. Store "visibility" status in some other class. Good choices are your own implementation of the Application o...