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How to delete (not cut) in Vim?
...
Use the "black hole register", "_ to really delete something: "_d.
Use "_dP to paste something and keep it available for further pasting.
For the second question, you could use <C-o>dw. <C-o> is used to execute a normal command without leaving ...
design a stack such that getMinimum( ) should be O(1)
... constant extra space and all operations are still O(1).
Stacks which are based instead on linked lists have other places you can borrow a bit from, for example in C the least significant bit of the next pointer, or in Java the type of the objects in the linked list. For Java this does mean there's...
MVVM in WPF - How to alert ViewModel of changes in Model… or should I?
...ke this:
// Attach EventHandler
PlayerModel.PropertyChanged += PlayerModel_PropertyChanged;
...
// When property gets changed in the Model, raise the PropertyChanged
// event of the ViewModel copy of the property
PlayerModel_PropertyChanged(object sender, PropertyChangedEventArgs e)
{
if (e....
Why dict.get(key) instead of dict[key]?
...ide a default value if the key is missing:
dictionary.get("bogus", default_value)
returns default_value (whatever you choose it to be), whereas
dictionary["bogus"]
would raise a KeyError.
If omitted, default_value is None, such that
dictionary.get("bogus") # <-- No default specified --...
How do you 'redo' changes after 'undo' with Emacs?
...
To undo: C-_
To redo after a undo: C-g C-_
Type multiple times on C-_ to redo what have been undone by C-_
To redo an emacs command multiple times, execute your command then type C-xz and then type many times on z key to repea...
How do I include a pipe | in my linux find -exec command?
...o use your top level shell to perform the piping like so:
find -name 'file_*' -follow -type f -exec zcat {} \; | agrep -dEOE 'grep'
In terms of efficiency this results costs one invocation of find, numerous invocations of zcat, and one invocation of agrep.
This would result in only a single agre...
What are the best practices for catching and re-throwing exceptions?
..., $host);
}
catch (Exception $e) {
echo "Error while connecting to database!";
die;
}
Logging or partial cleanup
Sometimes you do not know how to properly handle an exception inside a specific context; perhaps you lack information about the "big picture", but you do want to log the failur...
Find out time it took for a python script to complete execution
...test function"
L = []
for i in range(100):
L.append(i)
if __name__=='__main__':
from timeit import Timer
t = Timer("test()", "from __main__ import test")
print t.timeit()
Then to convert to minutes, you can simply divide by 60. If you want the script runtime in an easi...
Rename Files and Directories (Add Prefix)
...ll work for filenames with spaces in them:
for f in * ; do mv -- "$f" "PRE_$f" ; done
("--" is needed to succeed with files that begin with dashes, whose names would otherwise be interpreted as switches for the mv command)
...
How to log source file name and line number in Python
...='%Y-%m-%d:%H:%M:%S',
level=logging.DEBUG)
logger = logging.getLogger(__name__)
logger.debug("This is a debug log")
logger.info("This is an info log")
logger.critical("This is critical")
logger.error("An error occurred")
Generates this output:
2017-06-06:17:07:02,158 DEBUG [log.py:11] Thi...