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Techniques for Tracing Constraints
... and GHC complains could not deduce x ~ y for some x and y . You can usually throw GHC a bone and simply add the isomorphism to the function constraints, but this is a bad idea for several reasons:
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How to programmatically determine the current checked out Git branch [duplicate]
...ions/git-completion.bash does that for bash prompt in __git_ps1. Removing all extras like selecting how to describe detached HEAD situation, i.e. when we are on unnamed branch, it is:
branch_name="$(git symbolic-ref HEAD 2>/dev/null)" ||
branch_name="(unnamed branch)" # detached HEAD
branc...
How to express a One-To-Many relationship in Django
... sure there's a way to do this, so I'm not sure what I'm missing. I essentially have something like this:
8 Answers
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Is there a way to make R beep/play a sound at the end of a script?
...ion sounds in R which should work cross-platform. Run the following to install beepr and make a sound:
install.packages("beepr")
library(beepr)
beep()
More info at github: https://github.com/rasmusab/beepr
share
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How to use git with gnome-keyring integration
...iginal question) but I'm on Ubuntu. For git >= 2.11:
sudo apt-get install libsecret-1-0 libsecret-1-dev
cd /usr/share/doc/git/contrib/credential/libsecret
sudo make
git config --global credential.helper /usr/share/doc/git/contrib/credential/libsecret/git-credential-libsecret
For git < 2.11...
How to store arbitrary data for some HTML tags
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Which version of HTML are you using?
In HTML 5, it is totally valid to have custom attributes prefixed with data-, e.g.
<div data-internalid="1337"></div>
In XHTML, this is not really valid. If you are in XHTML 1.1 mode, the browser will probably complain about it, b...
In log4j, does checking isDebugEnabled before logging improve performance?
...using Log4J in my application for logging. Previously I was using debug call like:
16 Answers
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Getting a slice of keys from a map
...dited Sep 28 '17 at 4:19
Freedom_Ben
8,59888 gold badges4949 silver badges8080 bronze badges
answered Jan 8 '15 at 19:36
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How do I instantiate a Queue object in java?
...n't want to do this, but it's listed as an option for the sake of covering all the bases.
new Queue<Tree>() {
public Tree element() {
...
};
public boolean offer(Tree element) {
...
};
...
};
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Remove by _id in MongoDB console
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Very close. This will work:
db.test_users.deleteOne( {"_id": ObjectId("4d512b45cc9374271b02ec4f")});
i.e. you don't need a new for the ObjectId.
Also, note that in some drivers/tools, remove() is now deprecated and deleteOne or deleteMany should be used ins...