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Finding the type of an object in C++
I have a class A and another class that inherits from it, B. I am overriding a function that accepts an object of type A as a parameter, so I have to accept an A. However, I later call functions that only B has, so I want to return false and not proceed if the object passed is not of type B.
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Installed Ruby 1.9.3 with RVM but command line doesn't show ruby -v
...f /usr/share/ruby-rvm /etc/rvmrc /etc/profile.d/rvm.sh
open new terminal and validate environment is clean from old RVM settings (should be no output):
env | grep rvm
if there was output, try to open new terminal, if it does not help then restart your computer.
install RVM:
\curl -L https://g...
How can I filter a Django query with a list of values?
...
@OmkarDeshpande No
– DylanYoung
Nov 8 '18 at 16:47
@Dy...
How to use SSH to run a local shell script on a remote machine?
...ssh user@host2 <<'END2'
# Another bunch of commands on another host
wall <<'ENDWALL'
Error: Out of cheese
ENDWALL
ftp ftp.secureftp-test.com <<'ENDFTP'
test
test
ls
ENDFTP
END2
ENDSSH
You can actually have a conversation with some services like telnet, ftp, etc. But remember that...
How do I remove a key from a JavaScript object? [duplicate]
...
The delete operator allows you to remove a property from an object.
The following examples all do the same thing.
// Example 1
var key = "Cow";
delete thisIsObject[key];
// Example 2
delete thisIsObject["Cow"];
// Example 3
delete thisIsO...
CentOS 6.4下Squid代理服务器的安装与配置 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...|grep squid
3.2 如果未安装，则使用yum 方式安装
# yum -y install squid
3.3 设置开机自启动
# chkconfig --level 35 squid on //在3、5级别上自动运行squid服务
四、squid服务器的配置文件说明
squid 的主配置文件是 /etc/squid/squid.conf，...
Why would I ever use push_back instead of emplace_back?
...ob is to generate the code you wrote. The optimizing compiler's job is actually to generate the code you would have written if you were an expert on platform-specific optimizations and did not care about maintainability, just performance.
The actual difference between these two statements is that t...
Getting multiple keys of specified value of a generic Dictionary?
...tionary? Not that it is important or anything, just curious to if I understand things correctly here...
– Svish
Aug 4 '09 at 14:14
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Custom HTTP headers : naming conventions
... other words, you can keep using "X-" prefixed headers, but it's not officially recommended anymore and you may definitely not document them as if they are public standard.
Summary:
the official recommendation is to just name them sensibly without the "X-" prefix
you can keep using "X-" prefixe...
Avoid duplicates in INSERT INTO SELECT query in SQL Server
...ng to be faster than sub-selects. Perhaps that is for straight joins only, and not applicable to left joins.
– Duncan
Mar 25 '10 at 6:55
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