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What is the difference between Type and Class?
...primitives are classes (or more exactly structs).
– dalle
Jan 22 '09 at 7:10
4
@dalle: agreed, th...
How do I check if an element is hidden in jQuery?
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I actually found that the reverse logic words better: !$('selector').is(':hidden'); for some reason. Worth a try.
– Kzqai
Jan 5 '12 at 15:36
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Best way to build a Plugin system with Java
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First you need an interface that all plugins need to implement, e.g.
public interface Plugin {
public void load(PluginConfiguration pluginConfiguration);
public void run();
public void unload();
public JComponent getConfigurationPage();
}
...
Search and replace in bash using regular expressions
...'s are processed in order. Also, the g flag for the expression will match all occurrences in the input.
You can also pick your favorite tool using this method, i.e. perl, awk, e.g.:
echo "$MYVAR" | perl -pe 's/[a-zA-Z]/X/g and s/[0-9]/N/g'
This may allow you to do more creative matches... For ...
Android App Not Install. An existing package by the same name with a conflicting signature is alread
In my emulator, when I try to do an upgrade of my apk programmatically. I get:
14 Answers
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quick random row selection in Postgres
... make It sense to use a N less than SELECT COUNT(*)?, I mean, not use all the values in the table but only a part of them?
– Juan
Mar 14 '11 at 11:00
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What is the “-->” operator in C++?
...old value and 0 ..." to make it clearer. But this is nitpicking anyway. We all know what is meant.
– Johannes Schaub - litb
Jan 30 '10 at 17:42
38
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Remove element by id
...].map(n => n && n.remove());
These functions are available in all modern browsers (not IE). Read more on MDN.
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How can I add numbers in a Bash script?
...ntax
Using the external expr utility. Note that this is only needed for really old systems.
num=`expr $num1 + $num2` # Whitespace for expr is important
For floating point:
Bash doesn't directly support this, but there are a couple of external tools you can use:
num=$(awk "BEGIN {print $...
What's the difference between VARCHAR and CHAR?
...your content is a fixed size" it means the rows of your table must contain all fixed size fields. You get no performance improvement if you use CHAR against VARCHAR in one field, but the table contains other fields that are VARCHAR.
– Marco Demaio
May 20 '10 at...