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NSUserDefaults removeObjectForKey vs. setObject:nil
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Swift 3.0
The below answer is no longer the case when I tested this.
When set to nil the result is NSCFData being stored. Possibly an NSNull object reference, but I am not positive.
To completely remove a value for a key use UserDefaults.standard.removeObject(forKey: "YourDefaul...
Grep regex NOT containing string
...xpression), so the command is:
grep -P '(?<!1\.2\.3\.4).*Has exploded' test.log
Try this. It uses negative lookbehind to ignore the line if it is preceeded by 1.2.3.4. Hope that helps!
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Speed comparison with Project Euler: C vs Python vs Erlang vs Haskell
...n (they aren't the same). If you look in the GHC Base library you see mod tests for several conditions and adjusts the sign accordingly. (see modInt# in Base.lhs)
– Thomas M. DuBuisson
Aug 6 '11 at 5:23
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Connect Device to Mac localhost Server? [closed]
...on again, which solved the problem. Click Settings > Turn WI-FI Off.
I tested it by going to Safari on my iPhone and entering my host name or IP address. For example:
http://<name>.local or http://10.0.1.5
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How to test if a dictionary contains a specific key? [duplicate]
What's the cleanest way to test if a dictionary contains a key?
1 Answer
1
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How to remove item from a JavaScript object [duplicate]
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var test = {'red':'#FF0000', 'blue':'#0000FF'};
delete test.blue; // or use => delete test['blue'];
console.log(test);
this deletes test.blue
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Check if a string has a certain piece of text [duplicate]
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Here you go: ES5
var test = 'Hello World';
if( test.indexOf('World') >= 0){
// Found world
}
With ES6 best way would be to use includes function to test if the string contains the looking work.
const test = 'Hello World';
if (test.include...
Why am I getting “undefined reference to sqrt” error even though I include math.h header? [duplicate
...aries by environment, but in Linux/Unix, just add -lm to the command:
gcc test.c -o test -lm
The math library is named libm.so, and the -l command option assumes a lib prefix and .a or .so suffix.
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XP风格按钮的实现 - C/C++ - 清泛网 - 专注C/C++及内核技术
...：1.从互联网上下载XPButton类；2.创建基于对话框的MFC工程Test,将下载的XPButton.cpp和XPButt...方法一：利用XPButton类实现
具体操作步骤如下：
1.网上下载XPButton类；请参考《【工程源码】XPButton源码-XP风格按钮》
2.创建基于对话框的...
记一次数据库表自增长（Auto Increment）故障 - 数据库(内核) - 清泛网 - ...
...不妨创建一个测试表说明问题：
CREATE TABLE IF NOT EXISTS `test` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(100) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB;
然后插入一行问题数据：
INSERT INTO test (id, name) VALUES (2147483647, 'x');
结果导...