大约有 47,000 项符合查询结果（耗时：0.0646秒） [XML]
What is the difference between Ruby 1.8 and Ruby 1.9
...m not clear on the differences between the "current" version of Ruby (1.8) and the "new" version (1.9). Is there an "easy" or a "simple" explanation of the differences and why it is so different?
...
sed whole word search and replace
How do I search and replace whole words using sed?
6 Answers
6
...
How do the post increment (i++) and pre increment (++i) operators work in Java?
...=>
i=5 + 7 + 8; (a=8)
The main point is that ++a increments the value and immediately returns it.
a++ also increments the value (in the background) but returns unchanged value of the variable - what looks like it is executed later.
...
Performance of foreach, array_map with lambda and array_map with static function
...2 compare with mcfedr's answer below for additional results without XDebug and a more recent PHP version.
function lap($func) {
$t0 = microtime(1);
$numbers = range(0, 1000000);
$ret = $func($numbers);
$t1 = microtime(1);
return array($t1 - $t0, $ret);
}
function useForeach($numbers) {...
What is the difference in maven between dependency and plugin tags in pom xml?
I'm new to the maven tool, I have made a project with Spring and Hibernate and they are configured in pom.xml as plugins, but JUnit is tagged under dependency. My question is what is the logic behind one as a plugin and one as dependency ?
...
What is the canonical way to check for errors using the CUDA runtime API?
Looking through the answers and comments on CUDA questions, and in the CUDA tag wiki , I see it is often suggested that the return status of every API call should checked for errors. The API documentation contains functions like cudaGetLastError , cudaPeekAtLastError , and cudaGetErrorString , b...
What is the purpose and use of **kwargs?
...x when calling functions by constructing a dictionary of keyword arguments and passing it to your function:
>>> kwargs = {'first_name': 'Bobby', 'last_name': 'Smith'}
>>> print_keyword_args(**kwargs)
first_name = Bobby
last_name = Smith
The Python Tutorial contains a good explan...
In Clojure 1.3, How to read and write a file
I'd like to know the "recommended" way of reading and writing a file in clojure 1.3 .
6 Answers
...
What is the best way to ensure only one instance of a Bash script is running? [duplicate]
... a lockfile approach. If you acquire the lock, proceed else show a message and exit.
As an example:
[Terminal #1] $ lockfile -r 0 /tmp/the.lock
[Terminal #1] $
[Terminal #2] $ lockfile -r 0 /tmp/the.lock
[Terminal #2] lockfile: Sorry, giving up on "/tmp/the.lock"
[Terminal #1] $ rm -f /tmp/the....
Proper way to wait for one function to finish before continuing?
...function firstFunction(_callback){
// do some asynchronous work
// and when the asynchronous stuff is complete
_callback();
}
function secondFunction(){
// call first function and pass in a callback function which
// first function runs when it has completed
firstFunctio...