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Most efficient way to prepend a value to an array
...g-O performance if you are ok with modifying the array in-place. If you really can't mutate the original array then you would do something like the below snippet, which doesn't seem to be appreciably faster than your solution:
a.slice().unshift(0); // Use "slice" to avoid mutating "a".
[Edit 2]
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How can I create a Makefile for C projects with SRC, OBJ, and BIN subdirectories?
...JECTS) rule is problematic, because:
it's kind of indiscriminate, making all sources prerequisites of every object,
it often uses the wrong source (as you discovered with file1.o and file2.o)
it tries to build executables instead of stopping at objects, and
the name of the target (foo.o) is not...
How do I reverse a C++ vector?
...
All containers offer a reversed view of their content with rbegin() and rend(). These two functions return so-calles reverse iterators, which can be used like normal ones, but it will look like the container is actually rever...
Rails: How do I create a default value for attributes in Rails activerecord's model? [duplicate]
...
add_column :status, :string, :default => "P"
....
OR
You can use a callback, before_save
class Task < ActiveRecord::Base
before_save :default_values
def default_values
self.status ||= 'P' # note self.status = 'P' if self.status.nil? might be safer (per @frontendbeauty)
end
end
...
How do I unbind “hover” in jQuery?
...
Actually, the jQuery documentation has a more simple approach than the chained examples shown above (although they'll work just fine):
$("#myElement").unbind('mouseenter mouseleave');
As of jQuery 1.7, you are also able use $....
CSS: Animation vs. Transition
...ed, or vice versa.
If you want to perform something that does not specifically involve a start state and an end state, or you need more fine grain control over the keyframes in a transition, then you've got to use an animation.
...
Paused in debugger in chrome?
...nly takes a couple of hours (or less depending on your experience) to view all the options in the devTools UI and get comfortable with them. Please invest this time! It will help you immensely in your day-to-day debugging routine.
– CodeVortex
Aug 23 '16 at 8:3...
Bash if [ false ] ; returns true
...ce "false" is a non-empty string, the test command always succeeds. To actually run the command, drop the [ command.
if false; then
echo "True"
else
echo "False"
fi
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How do I find the most recent git commit that modified a file?
...ts looking at the history of specific files (and directories), so you can call it like this:
git log my/file.c
If you really only want to list the one most recent commit, for example to use it in a script, use the -n 1 option:
git log -n 1 --pretty=format:%H -- my/file.c
--pretty=format:%h tel...
getResourceAsStream returns null
...f the file you want to load inside the JAR (and thus also make sure it actually added to the JAR)
use either an absolute path: path starts at the root of the JAR
use an relative path: path starts at the package directory of the class you're calling getResource/ getResoucreAsStream
And try:
Lifepa...