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GCC -fPIC option
...ll required one more calculation (the function address) for each function call. So performance-wise, if not needed it is better not to use it.
– Roee Gavirel
Apr 21 at 6:41
ad...
Rails extending ActiveRecord::Base
...the ActiveSupport::Concern documentation for more details.
Create a file called active_record_extension.rb in the lib directory.
require 'active_support/concern'
module ActiveRecordExtension
extend ActiveSupport::Concern
# add your instance methods here
def foo
"foo"
end
# add y...
Difference between Covariance & Contra-variance
...ng function that associates one member of a set with another. More specifically, a mapping can be covariant or contravariant with respect to a relation on that set.
Consider the following two subsets of the set of all C# types. First:
{ Animal,
Tiger,
Fruit,
Banana }.
And second, this c...
Is there any performance reason to declare method parameters final in Java?
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I have seen Sun's compiler emit marginally shorter bytecode when the only difference between the two methods has been the "finality" of local variables. Micro-optimizations are a real thing, and compilers do actually make them. What really matters, of course, is ...
reStructuredText tool support
...fan of reStructuredText , however the tools that support it are scattered all over the Internet. The official tool list is incomplete and/or outdated, and can be updated only via commit privileges. For some time there was a comprehensive list at the Wikipedia reStructuredText page , but this app...
What is the maximum length of latitude and longitude? [closed]
...L) roughly follows the 180° longitude. A longitude with a positive value falls in the eastern hemisphere and negative value falls in the western hemisphere.
Decimal degrees precision
Six (6) decimal places precision in coordinates using decimal degrees notation is at a 10 cm (or 0.1 meter) resoluti...
sed edit file in place
... out if it is possible to edit a file in a single sed command without manually streaming the edited content into a new file and then renaming the new file to the original file name. I tried the -i option but my Solaris system said that -i is an illegal option. Is there a different way?
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Getting the first index of an object
...
For a one liner to work in all browsers including IE8 and below use for (var key in obj) if (obj.hasOwnProperty(key)) break; You'll then want to use the key variable
– Ally
Sep 6 '13 at 16:23
...
What exactly are unmanaged resources?
...
Managed resources basically means "managed memory" that is managed by the garbage collector. When you no longer have any references to a managed object (which uses managed memory), the garbage collector will (eventually) release that memory for you...
Git error: “Host Key Verification Failed” when connecting to remote repository
...as no way to know whether the host on the other end of the connection is really domain.com. (If the wrong key is in /etc, someone with administrative privileges will have to update the system-wide file.)
I strongly encourage you to consider having users authenticate with keys as well. That way, ssh...