大约有 17,000 项符合查询结果（耗时：0.0500秒） [XML]
Dynamic variable names in Bash
..." # outputs “lolilol”
echo "${!name%lol}" # outputs “loli”
# etc.
Unfortunately, there is no counterpart syntax for modifying the aliased variable. Instead, you can achieve assignment with one of the following tricks.
1a. Assigning with eval
eval is evil, but is also the simplest and ...
What are the differences between Helper and Utility classes?
...becoming useless. Examples: Vector3, RandomNumberGenerator, StringMatcher, etc...
A "helper" seems to be any class whose design is to aid another class. These may or may not depend on your project. If you're creating a GameNetworkClient class, you could say the GameNetworkConnection class is a 'he...
what happens when you type in a URL in browser [closed]
...
Attention: this is an extremely rough and oversimplified sketch, assuming the simplest possible HTTP request (no HTTPS, no HTTP2, no extras), simplest possible DNS, no proxies, single-stack IPv4, one HTTP request only, a simple HTTP server on the other end, and no problems in any ste...
Advantages of std::for_each over for loop
... your mind to the rest of the STL-algorithms, like find_if, sort, replace, etc and these won't look so strange anymore. This can be a huge win.
Update 1:
Most importantly, it helps you go beyond for_each vs. for-loops like that's all there is, and look at the other STL-alogs, like find / sort / pa...
MySQL: Large VARCHAR vs. TEXT?
... If all the columns are short and predictable (ex: MAC address, IMEI, etc... are things that never change) then use CHAR columns and you can make your row size fixed, which should speed things up considerably if using MyISAM, possibly also InnoDb although I am not sure about it.
...
wildcard * in CSS for classes
...I'm styling with .tocolor , but I also need the unique identifier 1,2,3,4 etc. so I'm adding that it as another class tocolor-1 .
...
Image comparison - fast algorithm
... if a good match is found at the faster level.
file-hash based (md5,sha1,etc) for exact duplicates
perceptual hashing (phash) for rescaled images
feature-based (SIFT) for modified images
I am having very good results with phash. The accuracy is good for rescaled images. It is not good ...
Conventions for exceptions or error codes
...tion can then contain code to check whether the file exists, or is locked, etc)
share
|
improve this answer
|
follow
|
...
How to initialize log4j properly?
...sed to initialize itself, which loggers / appenders got configured and how etc.
The configuration file can be a java properties file or an xml file. Here is a sample of the properties file format taken from the log4j intro documentation page:
log4j.rootLogger=debug, stdout, R
log4j.appender.stdo...
What is the difference between the kernel space and the user space?
...r processes have to use the predefined system calls i.e. open, read, write etc. Also, the C library functions like printf call the system call write in turn.
The system calls act as an interface between the user processes and the kernel processes. The access rights are placed on the kernel space i...