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Efficient way to remove keys with empty strings from a dict
I have a dict and would like to remove all the keys for which there are empty value strings.
17 Answers
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SOAP server and client application VCL+indy demo for Delphi XE?
...2007 era SOAP demos from the WebServices folder, now updated for Delphi XE and XE2, including converting the old WAD servers into new INDY VCL servers. You'd think that was impressive, except it's not. It's really easy. Just use the wizard to create a new project, and then add the web service inter...
git: How do I get the latest version of my code?
...racked or generated files or subrepositories which just happen to be here) and just want a copy from the repo:
git reset --hard HEAD
git clean -xffd
git pull
Again, this will nuke any changes you've made locally so use carefully. Think about rm -Rf when doing this.
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namedtuple and default values for optional keyword arguments
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I subclassed namedtuple and overrode the __new__ method:
from collections import namedtuple
class Node(namedtuple('Node', ['value', 'left', 'right'])):
__slots__ = ()
def __new__(cls, value, left=None, right=None):
return super(Nod...
MySQL: Fastest way to count number of rows
...mysql side?
If the COUNT(*) is slow, you should run EXPLAIN on the query, and check if indexes are really used, and where should they be added.
The following is not the fastest way, but there is a case, where COUNT(*) doesn't really fit - when you start grouping results, you can run into problem...
What is the difference between a var and val definition in Scala?
What is the difference between a var and val definition in Scala and why does the language need both? Why would you choose a val over a var and vice versa?
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How do you clear the SQL Server transaction log?
I'm not a SQL expert, and I'm reminded of the fact every time I need to do something beyond the basics. I have a test database that is not large in size, but the transaction log definitely is. How do I clear out the transaction log?
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How to exit from Python without traceback?
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You are presumably encountering an exception and the program is exiting because of this (with a traceback). The first thing to do therefore is to catch that exception, before exiting cleanly (maybe with a message, example given).
Try something like this in your main r...
Android List View Drag and Drop sort
...ords in a listview that I want the user to be able to re-sort using a drag and drop method. I have seen this implemented in other apps, but I have not found a tutorial for it. It must be something that others need as well. Can anyone point me to some code for doing this?
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virtualenv --no-site-packages and pip still finding global packages?
...on that virtualenv --no-site-packages would create a completely separate and isolated Python environment, but it doesn't seem to.
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