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Why must wait() always be in synchronized block
We all know that in order to invoke Object.wait() , this call must be placed in synchronized block, otherwise an IllegalMonitorStateException is thrown. But what's the reason for making this restriction? I know that wait() releases the monitor, but why do we need to explicitly acquire the mon...
Node.js check if file exists
...
A easier way to do this synchronously.
if (fs.existsSync('/etc/file')) {
console.log('Found file');
}
The API doc says how existsSync work:
Test whether or not the given path exists by checking with the file system.
...
How to identify server IP address in PHP
... @andreas It shouldn't. The local hostname should be in the /etc/hosts file and will be fast - although it might just be 127.0.0.1. If it does have to call DNS then it will be slow like you say.
– Ariel
Feb 12 '15 at 10:39
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Why do we need C Unions?
... follows:
reg.dword = 0x12345678;
reg.bytes.byte3 = 4;
Endianness (byte order) and processor architecture are of course important.
Another useful feature is the bit modifier:
typedef union
{
struct {
unsigned char b1:1;
unsigned char b2:1;
unsigned char b3:1;
...
Why does one often see “null != variable” instead of “variable != null” in C#?
In c#, is there any difference in the excecution speed for the order in which you state the condition?
9 Answers
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Cleaning up the iPhone simulator
...one app)
All the notes from others apply about being a good upgradable app etc. (I personally found this useful nonetheless b/c I have development mode switches that reload a database in a specific state I was trying to do some consistent robustness/error handling on)
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Why are variables “i” and “j” used for counters?
... real. This meant that I was the first integer variable, and J the second, etc., so they fell towards use in loops.
share
answered Nov 9 '10 at 19:48
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What is the 'pythonic' equivalent to the 'fold' function from functional programming?
...duce with non-associative operators is considered bad style.
Using higher-order functions is quite pythonic; it makes good use of Python's principle that everything is an object, including functions and classes. You are right that lambdas are frowned upon by some Pythonistas, but mostly because the...
start MySQL server from command line on Mac OS Lion
...rt-files/mysql.server stop
On Linux start/stop from the command line:
/etc/init.d/mysqld start
/etc/init.d/mysqld stop
/etc/init.d/mysqld restart
Some Linux flavours offer the service command too
# service mysqld start
# service mysqld stop
# service mysqld restart
or
# service mysql...
Regex exactly n OR m times
...y the way stated in the question and it does work but there's a catch:
The order of the quantities matters. Consider this:
#[a-f0-9]{6}|#[a-f0-9]{3}
This will find all occurences of hex colour codes (they're either 3 or 6 digits long). But when I flip it around like this
#[a-f0-9]{3}|#[a-f0-9]{...