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typeof !== “undefined” vs. != null
...gument, or as a global variable), I think the best way to do it is:
if (my_variable === undefined)
jQuery does it, so it's good enough for me :-)
Otherwise, you'll have to use typeof to avoid a ReferenceError.
If you expect undefined to be redefined, you could wrap your code like this:
(functi...
Bash array with spaces in elements
...through its indices, like so, it works if I add the elements either numerically or with escapes:
for ((i = 0; i < ${#FILES[@]}; i++))
do
echo "${FILES[$i]}"
done
Any of these declarations of $FILES should work:
FILES=(2011-09-04\ 21.43.02.jpg
2011-09-05\ 10.23.14.jpg
2011-09-09\ 12.31.16....
What is the difference between int, Int16, Int32 and Int64?
...al, on modern computers, an int16 takes as much space as an int32 (and actually an int64) because in order for most operations to be efficient, we pad around the data to make accesses aligned to 32 or 64 bit boundaries (in 32 or 64 bit modes respectively). This is because unaligned accesses are ridi...
服务器保持大量TIME_WAIT和CLOSE_WAIT的解决方法 - C/C++ - 清泛网 - 专注C/C++及内核技术
服务器保持大量TIME_WAIT和CLOSE_WAIT的解决方法昨天解决了一个HttpClient调用错误导致的服务器异常，具体过程如下：http: blog.csdn.net shootyou article details 6615051里头的分析过...昨天解决了一个HttpClient调用错误导致的服务器异常，具体...
How can I get the SQL of a PreparedStatement?
...
Although this is functionally true, there's nothing preventing utility code from reconstructing an equivalent unprepared statement. For example, in log4jdbc: "In the logged output, for prepared statements, the bind arguments are automatically insert...
What is the Swift equivalent of respondsToSelector?
...e are multiple candidates: let theMethod = delegate.userNotificationCenter(_:willPresent:withCompletionHandler:)
– Cœur
May 4 '18 at 8:47
...
How to dynamically update a ListView on Android [closed]
...lns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<!-- Pretty hint text, and maxLines -->
<EditText android:id="@+building_list/search_box"
android...
How do you find the row count for all your tables in Postgres
I'm looking for a way to find the row count for all my tables in Postgres. I know I can do this one table at a time with:
...
QuotaExceededError: Dom exception 22: An attempt was made to add something to storage that exceeded
...ode browsing. While in private browsing, local storage is not available at all.
One solution is to warn the user that the app needs non-private mode to work.
UPDATE: This has been fixed in Safari 11, so the behaviour is now aligned with other browsers.
...
What are the options for storing hierarchical data in a relational database? [closed]
...s a result, most people end up having to settle for one or the other especially if there are more than, say, a lousy 100,000 nodes or so. Using the push stack method can take a whole day to do the conversion on what MLM'ers would consider to be a small million node hierarchy.
I thought I'd give Ce...