大约有 40,000 项符合查询结果（耗时：0.0410秒） [XML]
django - why is the request.POST object immutable?
...QueryDict class, which implements a full set of mutation methods including __setitem__, __delitem__, pop and clear. It implements immutability by checking a flag when you call one of the mutation methods. And when you call the copy method you get another QueryDict instance with the mutable flag turn...
Concurrent.futures vs Multiprocessing in Python 3
...o make it work:
from concurrent.futures import ProcessPoolExecutor
def pool_factorizer_map(nums, nprocs):
# Let the executor divide the work among processes by using 'map'.
with ProcessPoolExecutor(max_workers=nprocs) as executor:
return {num:factors for num, factors in
...
How do you get a Golang program to print the line number of the error it just called?
... // the error happened, 0 = this function, we don't want that.
_, fn, line, _ := runtime.Caller(1)
log.Printf("[error] %s:%d %v", fn, line, err)
b = true
}
return
}
//this logs the function name as well.
func FancyHandleError(err error) (b bool) {
if err != n...
Multiple Updates in MySQL
...teresting look at the functionality of casing...
– me_
Feb 7 '17 at 21:55
1
@user2536953 , it can...
What is the volatile keyword useful for?
... volatile:
public class Singleton {
private static volatile Singleton _instance; // volatile variable
public static Singleton getInstance() {
if (_instance == null) {
synchronized (Singleton.class) {
if (_instance == null)
_instance = ...
How to define hash tables in Bash?
...are the answer by introducing the concepts:
First, indirection.
$ animals_moo=cow; sound=moo; i="animals_$sound"; echo "${!i}"
cow
Secondly, declare:
$ sound=moo; animal=cow; declare "animals_$sound=$animal"; echo "$animals_moo"
cow
Bring them together:
# Set a value:
declare "array_$index=$...
JavaScript private methods
... prototype:
function Restaurant() {
var myPrivateVar;
var private_stuff = function() { // Only visible inside Restaurant()
myPrivateVar = "I can set this here!";
}
this.use_restroom = function() { // use_restroom is visible to all
private_stuff();
}
this...
String, StringBuffer, and StringBuilder
... 2;
if (newCapacity < 0) {
newCapacity = Integer.MAX_VALUE;
} else if (minimumCapacity > newCapacity) {
newCapacity = minimumCapacity;
}
value = Arrays.copyOf(value, newCapacity);
}
A best practice is to initialize the StringBuilder/Buffer ...
How do I check if a string is unicode or ascii?
... it raises a UnicodeDecodeError exception, it wasn't valid.
>>> u_umlaut = b'\xc3\x9c' # UTF-8 representation of the letter 'Ü'
>>> u_umlaut.decode('utf-8')
u'\xdc'
>>> u_umlaut.decode('ascii')
Traceback (most recent call last):
File "<stdin>", line 1, in <m...
Integrating MySQL with Python in Windows
... x64 but while importing MySQLdb I'm getting 'ImportError: No module named _mysql_windows.api' error. pls anyone help me to solve this issue.
– Vilva
Aug 3 '12 at 12:15
4
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