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How do you test functions and closures for equality?
...s Lattner wrote on the developer forums:
This is a feature we intentionally do not want to support. There are
a variety of things that will cause pointer equality of functions (in
the swift type system sense, which includes several kinds of closures)
to fail or change depending on optimiz...
How to check if object (variable) is defined in R?
...
heh. Happens to me all the time when I am testing out examples before posting, Gavin or Josh have already answered it.
– Maiasaura
Feb 20 '12 at 22:17
...
How to check if an element is in an array
...ins function has been made into a pair of extension method on Array, which allow you to do either of:
let a = [ 1, 2, 3, 4 ]
a.contains(2) // => true, only usable if Element : Equatable
a.contains { $0 < 1 } // => false
...
Avoid duplicates in INSERT INTO SELECT query in SQL Server
...
Using NOT EXISTS:
INSERT INTO TABLE_2
(id, name)
SELECT t1.id,
t1.name
FROM TABLE_1 t1
WHERE NOT EXISTS(SELECT id
FROM TABLE_2 t2
WHERE t2.id = t1.id)
Using NOT IN:
INSERT INTO TABLE_2
(id, name)
SELECT t...
`Apache` `localhost/~username/` not working
...s:
<Directory "/Users/kevin/Sites/">
Options Indexes MultiViews
AllowOverride None
Require all granted
</Directory>
Make sure to restart the Apache server afterwards with:
sudo apachectl restart
share
...
What is the Java string pool and how is “s” different from new String(“s”)? [duplicate]
...terned. The
distinct values are stored in a string
intern pool.
Basically, a string intern pool allows a runtime to save memory by preserving immutable strings in a pool so that areas of the application can reuse instances of common strings instead of creating multiple instances of it.
As an ...
How to extract a git subdirectory and make a submodule out of it?
...
Nowadays there's a much easier way to do it than manually using git filter-branch: git subtree
Installation
NOTE git-subtree is now part of git (if you install contrib) as of 1.7.11, so you might already have it installed. You may check by executing git subtree.
To install...
“No such file or directory” error when executing a binary
I was installing a binary Linux application on Ubuntu 9.10 x86_64. The app shipped with an old version of gzip (1.2.4), that was compiled for a much older kernel:
...
腾讯Tencent开源框架介绍（持续更新） - 开源 & Github - 清泛网 - 专注C/C++及内核技术
...h>
#include <stdio.h>
#include <stdlib.h>
#include <queue>
#include "co_routine.h"
using namespace std;
/**
* 本实例是对条件变量的展示，其作用类似于pthread_cond_wait
*/
struct stTask_t
{
int id;
};
struct stEnv_t
{
stCoCond_t* cond;
queue<stTask_t*> task_queue...
GitHub pages are not updating
..., but the new article isn't showing up there. When I execute the server locally, a post lives at localhost:4000/posts/the-price-of-inconsistent-code/ . However, when I go to http://maltzj.github.io/posts/the-price-of-inconsistent-code I get a 404. I also added a new file which should live at htt...