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Is it possible to “await yield return DoSomethingAsync()”
...
What you are describing can be accomplished with the Task.WhenAll method. Notice how the code turns into a simple one-liner. What happens is that each individual url begins downloading and then WhenAll is used combine those operations into a single Task which can be awaited.
Task<IE...
What's the difference between VARCHAR and CHAR?
...your content is a fixed size" it means the rows of your table must contain all fixed size fields. You get no performance improvement if you use CHAR against VARCHAR in one field, but the table contains other fields that are VARCHAR.
– Marco Demaio
May 20 '10 at...
What's the best practice to “git clone” into an existing folder?
...hanks! Though this is missing a step like "git checkout -- ." as it thinks all the files are deleted, right?
– mrooney
Dec 15 '12 at 19:39
2
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ATL正则表达式库使用 - C/C++ - 清泛网 - 专注C/C++及内核技术
...f (!reUrl.Match( "http://search.microsoft.com/us/Search.asp?qu=atl&boolean=ALL#results",
&mcUrl))
{
// Unexpected error.
return 0;
}
for (UINT nGroupIndex = 0; nGroupIndex < mcUrl.m_uNumGroups;
++nGroupIndex)
{
const CAtlREMatchContext<>::RECHAR...
adding header to python requests module
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You can also do this to set a header for all future gets for the Session object, where x-test will be in all s.get() calls:
s = requests.Session()
s.auth = ('user', 'pass')
s.headers.update({'x-test': 'true'})
# both 'x-test' and 'x-test2' are sent
s.get('http://h...
Why are Python lambdas useful? [closed]
...ut lambda functions? Like
lambda x: x**2 + 2*x - 5
Those things are actually quite useful. Python supports a style of programming called functional programming where you can pass functions to other functions to do stuff. Example:
mult3 = filter(lambda x: x % 3 == 0, [1, 2, 3, 4, 5, 6, 7, 8, 9])...
SSL_connect returned=1 errno=0 state=SSLv3 read server certificate B: certificate verify failed
...L Certificate Authority (CA) bundle. You can do this with:
sudo port install curl-ca-bundle [if you are using MacPorts]
or just pull it down directly wget http://curl.haxx.se/ca/cacert.pem
Execute the ruby code that is trying to verify the SSL certification: SSL_CERT_FILE=/opt/local/etc/certs/ca...
Why do x86-64 instructions on 32-bit registers zero the upper part of the full 64-bit register?
...he CPU would have to wait on. The register renaming mechanism would essentially be defeated if it wasn't done that way.
This way you can write fast code using 32-bit values in 64-bit mode without having to explicitly break dependencies all the time. Without this behaviour, every single 32-bit instr...
Import file size limit in PHPMyAdmin
I have changed all the php.ini parameters I know:
upload_max_filesize , post_max_size .
27 Answers
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Deep null checking, is there a better way?
...'d say
cake?.frosting?.berries?.loader
and the compiler would generate all the short-circuiting checks for you.
It didn't make the bar for C# 4. Perhaps for a hypothetical future version of the language.
Update (2014):
The ?. operator is now planned for the next Roslyn compiler release. Note ...