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std::unique_lock or std::lock_guard?
...
The difference is that you can lock and unlock a std::unique_lock. std::lock_guard will be locked only once on construction and unlocked on destruction.
So for use case B you definitely need a std::unique_lock for the condition variable. In case A it depends ...
Removing transforms in SVG files
I have been struggling with this for a while, and can't seem to find an answer (that works) anywhere. I have an SVG file which looks like this:
...
Regex not operator
... In the edit of your question you put the {4} outside the lookahead and in this comment you put it inside: which one did you try? Also: if you want (20019) to match, then you must add the \) inside your lookahead: \((?![\d]{4}\))[0-9a-zA-z _\.\-:]+\)
– Joachim Sauer
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Looping through localStorage in HTML5 and JavaScript
...ock, just looking at, it should work. Is there a reason I should use parse and not eval? I'm using eval now to get it from a string, but is parse better/faster?
– Oscar Godson
Jun 29 '10 at 21:15
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What is lexical scope?
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I understand them through examples. :)
First, lexical scope (also called static scope), in C-like syntax:
void fun()
{
int x = 5;
void fun2()
{
printf("%d", x);
}
}
Every inner level can access its outer l...
How do I convert seconds to hours, minutes and seconds?
...his is the best way, IMHO, as you can then use arithmetic on the timedelta and any datetime objects.
– Matthew Schinckel
Apr 22 '09 at 3:13
13
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How to retry after exception?
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Do a while True inside your for loop, put your try code inside, and break from that while loop only when your code succeeds.
for i in range(0,100):
while True:
try:
# do stuff
except SomeSpecificException:
continue
break
...
How to set a Django model field's default value to a function call / callable (e.g., a date relative
...e class.
PRE Django 1.7
Django lets you pass a callable as the default, and it will invoke it each time, just as you want:
from datetime import datetime, timedelta
class MyModel(models.Model):
# default to 1 day from now
my_date = models.DateTimeField(default=lambda: datetime.now() + timedel...
Rails: fields_for with index?
...uestion do |fq| %>
# here you have both the 'question' object and the current 'index'
<% end %>
<% end %>
From:
http://railsapi.com/doc/rails-v3.0.4/classes/ActionView/Helpers/FormHelper.html#M006456
It’s also possible to specify the
instance to be used:
<%= fo...
Reliable method to get machine's MAC address in C#
...it is running using C#. Application will need to work on XP/Vista/Win7 32 and 64 bit as well as on those OSs but with a foreign language default. Many of the C# commands and OS queries don't work across OS. Any ideas? I have been scraping the output of "ipconfig /all" but this is terribly unreli...