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mysql - how many columns is too many?
...uestion - do you think the number of votes next to SO question / answer is calculated as select count(*) from votes every time or do you think that perhaps it's denormalized? Does that make SO database bad and Jeff Atwood crazy?
– ChssPly76
Sep 25 '09 at 19:06
...
What is the difference between .*? and .* regular expressions?
...greedy - it will match all the way to the end, and then backtrack until it can match 1, leaving you with 1010000000001.
.*? is non-greedy. * will match nothing, but then will try to match extra characters until it matches 1, eventually matching 101.
All quantifiers have a non-greedy mode: .*?, .+?,...
What's the difference between “Write-Host”, “Write-Output”, or “[console]::WriteLine”?
...ds to Out-Default at the end.
Test-Output
You'll need to enclose the concatenation operation in parentheses, so that PowerShell processes the concatenation before tokenizing the parameter list for Write-Host, or use string interpolation
write-host ("count=" + $count)
# or
write-host "count=$coun...
What are some uses of decltype(auto)?
...generic code
For non-generic code, like the initial example you gave, you can manually select to get a reference as a return type:
auto const& Example(int const& i)
{
return i;
}
but in generic code you want to be able to perfectly forward a return type without knowing whether you...
Maven: how to override the dependency added by a library
...
it's not clear how I can specify the version since I don't declare a dependency on D. Also, the first link you provided has "This document describes the rest of the requirements for dependency management that have NOT yet been implemented for Mav...
Understanding the difference between __getattr__ and __getattribute__
...bute would become getattr(instance, attribute_name). Using this model, we can get the attribute by supplying the attribute_name as a string.
Use of __getattr__
You can also tell a class how to deal with attributes which it doesn't explicitly manage and do that via __getattr__ method.
Python will...
How can I recover a lost commit in Git?
...s your friend. Find the commit that you want to be on in that list and you can reset to it (for example:git reset --hard e870e41).
(If you didn't commit your changes... you might be in trouble - commit early, and commit often!)
...
Setup RSpec to test a gem (not Rails)
...the added generator of rspec-rails to setup RSpec for testing a Rails application. But how about adding RSpec for testing a gem in development?
I am not using jeweler or such tools. I just used Bundler ( bundle gem my_gem ) to setup the structure for the new gem and edit the *.gemspec manually.
I al...
Does JavaScript have “Short-circuit” evaluation?
...uit" evaluation.
if (true == true || foo.foo){
// Passes, no errors because foo isn't defined.
}
Live DEMO
if (false && foo.foo){
// Passes, no errors because foo isn't defined.
}
Live DEMO
share
...
OSGi, Java Modularity and Jigsaw
...
First understand that Jigsaw's primary use case is to modularise the JRE itself. As a secondary goal it will offer a module system that may be used by other Java libraries and applications.
My position is that something like Jigsaw is probably necessary for the JRE o...