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Remove duplicate elements from array in Ruby
...
Just another alternative if anyone cares.
You can also use the to_set method of an array which converts the Array into a Set and by definition, set elements are unique.
[1,2,3,4,5,5,5,6].to_set => [1,2,3,4,5,6]
...
Calling Objective-C method from C++ member function?
...hat C++ class a objective-C function [context renderbufferStorage:GL_RENDERBUFFER fromDrawable:(CAEAGLLayer*)self.layer]; which I cannot do in C++ syntax.
...
How to limit the maximum value of a numeric field in a Django model?
...go.db import models
class IntegerRangeField(models.IntegerField):
def __init__(self, verbose_name=None, name=None, min_value=None, max_value=None, **kwargs):
self.min_value, self.max_value = min_value, max_value
models.IntegerField.__init__(self, verbose_name, name, **kwargs)
...
How do you create nested dict in Python?
...he following:
d = {} # can use defaultdict(dict) instead
for row in file_map:
# derive row key from something
# when using defaultdict, we can skip the next step creating a dictionary on row_key
d[row_key] = {}
for idx, col in enumerate(row):
d[row_key][idx] = col
Ac...
How can I color Python logging output?
...oreground with 30
#These are the sequences need to get colored ouput
RESET_SEQ = "\033[0m"
COLOR_SEQ = "\033[1;%dm"
BOLD_SEQ = "\033[1m"
def formatter_message(message, use_color = True):
if use_color:
message = message.replace("$RESET", RESET_SEQ).replace("$BOLD", BOLD_SEQ)
else:
...
C++中判断文件、目录是否存在的几种方法 - C/C++ - 清泛网 - 专注C/C++及内核技术
...
if(fh == NULL)
{
printf("%s","can not open the file");
}
三、_access
当然C中还有一种方式是直接调用c的函数库。
就是函数 int _access(const char* path,int mode);
这个函数的功能十分强大。
可以看看msdn的详细介绍
#include <io.h>
#include ...
Getting the name of a child class in the parent class (static context)
...ot possible. in php4 you could implement a terrible hack (examine the debug_backtrace()) but that method does not work in PHP5. references:
30423
37684
34421
edit: an example of late static binding in PHP 5.3 (mentioned in comments). note there are potential problems in it's current implementat...
What is the difference between shallow copy, deepcopy and normal assignment operation?
... @grc But I have tried an example(I remove the new line here.) list_=[[1,2],[3,4]] newlist = list_.copy() list_[0]=[7,8] print(list_) print(newlist) The newlist still display [[1, 2], [3, 4]]. But list_[0] is a list which is mutable.
– Alston
Nov 12 '16...
Rails: around_* callbacks
...classes/ActiveRecord/Callbacks.html , but don't understand when the around_* callbacks are triggered in relation to before_* and after_* .
...
How do I perform the SQL Join equivalent in MongoDB?
...ttps://docs.mongodb.org/master/reference/operator/aggregation/lookup/#pipe._S_lookup
From the docs:
{
$lookup:
{
from: <collection to join>,
localField: <field from the input documents>,
foreignField: <field from the documents of the "from" collection>...