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Proper use of 'yield return'
...ld keyword is one of those keywords in C# that continues to mystify me, and I've never been confident that I'm using it correctly.
...
Is volatile expensive?
...LoadLoad or a LoadStore barrier. Further down the page I see that LoadLoad and LoadStore are effectively no-ops on X86 CPUs. Does this mean that volatile read operations can be done without a explicit cache invalidation on x86, and is as fast as a normal variable read (disregarding the reordering co...
Python to print out status bar and percentage
...character (carriage return) resets the cursor to the beginning of the line and allows you to write over what was previously on the line.
from time import sleep
import sys
for i in range(21):
sys.stdout.write('\r')
# the exact output you're looking for:
sys.stdout.write("[%-20s] %d%%" %...
“[notice] child pid XXXX exit signal Segmentation fault (11)” in apache error.log [closed]
...
Attach gdb to one of the httpd child processes and reload or continue working and wait for a crash and then look at the backtrace. Do something like this:
$ ps -ef|grep httpd
0 681 1 0 10:38pm ?? 0:00.45 /Applications/MAMP/Library/bin/httpd -k start
501...
Synchronizing a local Git repository with a remote one
...er in these repositories, we override the local ones with the remote ones, and if there are files in local repositories that do not exist in the remote, the local files get removed.
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git discard all changes and pull from upstream
How do I fetch upstream repo and make it replace master? I only have one branch on my repo, which is master, and I completely messed it up, so I basically need to start over from the upstream. I think init will do the job, but is there an easier way?
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How to push new branch without history
I have git repo with two unrelated branches, master and configs.
I've created configs, purged all the files and then placed in configuration files only.
Now I want to push this on remote repo, but as it were new, empty branch (without logs of all my changes and old revisions of original branch).
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Form inside a table
I'm including some forms inside a HTML table to add new rows and update current rows. The problem that I'm getting is that when I inspect the forms in my dev tools, I see that the form elements are closed immediately after opening (inputs, etc are not included within the form).
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SQLAlchemy: Creating vs. Reusing a Session
...on_commit=False) anytime you needed a new Session, except that its verbose and redundant, and I wanted to stop the proliferation of small-scale "helpers" that each approached the issue of this redundancy in some new and more confusing way.
So sessionmaker() is just a tool to help you create Session...
Why does 2 == [2] in JavaScript?
...alueOf().toString())
where valueOf() for arrays returns the array itself and the string-representation of a one-element array is the string representation of the single element.
This also explains the third example as [[[[[[[2]]]]]]].toString() is still just the string 2.
As you can see, there's...