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Evaluate empty or null JSTL c tags
...out those ${} things (the Expression Language, which is a separate subject from JSTL), check here.
See also:
How does EL empty operator work in JSF?
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Parse v. TryParse
... Parse throws a number of different exceptions so if all it had was a bool from TryParse then it wouldn't know which one to throw.
– Greg Beech
Jan 22 '09 at 8:42
5
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Clang vs GCC for my Linux Development project
...lt;(std::ostream& out, Student const& s) {
^
In file included from /tmp/webcompile/_25327_1.cc:1:
In file included from /usr/include/c++/4.3/string:49:
In file included from /usr/include/c++/4.3/bits/localefwd.h:47:
/usr/include/c++/4.3/iosfwd:134:33: note: previous definition is here
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Why historically do people use 255 not 256 for database field magnitudes?
...onstrained otherwise). Most systems treat such an empty string as distinct from NULL, but some systems (notably Oracle) treat an empty string identically to NULL. For systems where an empty string is not NULL, an additional bit somewhere in the row would be needed to indicate whether the value shoul...
Convert datetime to Unix timestamp and convert it back in python
...f your original naive datetime was UTC, the way to recover it is to use utcfromtimestamp instead of fromtimestamp.
On the other hand, if your original naive datetime was local, you shouldn't have subtracted a UTC timestamp from it in the first place; use datetime.fromtimestamp(0) instead.
Or, if y...
AsyncTask and error handling on Android
I'm converting my code from using Handler to AsyncTask . The latter is great at what it does - asynchronous updates and handling of results in the main UI thread. What's unclear to me is how to handle exceptions if something goes haywire in AsyncTask#doInBackground .
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How do you trigger a block after a delay, like -performSelector:withObject:afterDelay:?
...cept no parameters, but you can just let the block capture those variables from your local scope instead.
int parameter1 = 12;
float parameter2 = 144.1;
// Delay execution of my block for 10 seconds.
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, 10 * NSEC_PER_SEC), dispatch_get_main_queue(), ^{
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Should I avoid the use of set(Preferred|Maximum|Minimum)Size methods in Java Swing?
...Pane);
frmtest.pack();
// User's preference should be read from java.util.prefs.Preferences
frmtest.setSize(400, 300);
frmtest.setLocationRelativeTo(null);
frmtest.setVisible(true);
list.get(0).requestFocusInWindow();
}
private static class Fo...
Make: how to continue after a command fails?
...with rm, but are applicable to any other command you need to ignore errors from (i.e. mkdir).
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What is the difference between 'typedef' and 'using' in C++11?
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They are equivalent, from the standard (emphasis mine) (7.1.3.2):
A typedef-name can also be introduced by an alias-declaration. The
identifier following the using keyword becomes a typedef-name and the
optional attribute-specifier-seq fo...