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Dictionaries and default values
...collections import defaultdict
a = defaultdict(lambda: "default", key="some_value")
a["blabla"] => "default"
a["key"] => "some_value"
You can pass any ordinary function instead of lambda:
from collections import defaultdict
def a():
return 4
b = defaultdict(a, key="some_value")
b['absent...
Synchronization vs Lock
java.util.concurrent API provides a class called as Lock , which would basically serialize the control in order to access the critical resource. It gives method such as park() and unpark() .
...
How does “cat
...
This is called heredoc format to provide a string into stdin. See https://en.wikipedia.org/wiki/Here_document#Unix_shells for more details.
From man bash:
Here Documents
This type of redirection instructs the shell to read...
How do I remove an item from a stl vector with a certain value?
...n for stl vector, and noticed there was no method on the vector class that allowed the removal of an element with a certain value. This seems like a common operation, and it seems odd that there's no built in way to do this.
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WPF Button with Image
I'm trying to attach an image on a button in WPF, however this code fails. Seems strange after similar code would work perfectly in Mozilla XUL.
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Storing SHA1 hash values in MySQL
...INARY(20) and CHAR(40).
CREATE TABLE `binary` (
`id` int unsigned auto_increment primary key,
`password` binary(20) not null
);
CREATE TABLE `char` (
`id` int unsigned auto_increment primary key,
`password` char(40) not null
);
With million of records binary(20) takes 44.56M, whil...
Map function in MATLAB?
I'm a little surprised that MATLAB doesn't have a Map function, so I hacked one together myself since it's something I can't live without. Is there a better version out there? Is there a somewhat-standard functional programming library for MATLAB out there that I'm missing?
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Is there an alternative to bastard injection? (AKA poor man's injection via default constructor)
... well-known pattern, but I'll grant that overloaded constructors are marginally more 'in your face' :)
– Mark Seemann
Jul 20 '11 at 7:21
5
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What is the Swift equivalent of -[NSObject description]?
...bjective-C, one can add a description method to their class to aid in debugging:
7 Answers
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HAproxy - Web负载均衡解决方案 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...参数的设置
log 127.0.0.1 local0 info
# log语法：log <address_1>[max_level_1] # 全局的日志配置，使用log关键字，指定使用127.0.0.1上的syslog服务中的local0日志设备，记录日志等级为info的日志
user haproxy
group haproxy
# 设置运行hapro...