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How can I check the size of a collection within a Django template?
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See https://docs.djangoproject.com/en/stable/ref/templates/builtins/#if : just use, to reproduce their example:
{% if athlete_list %}
Number of athletes: {{ athlete_list|length }}
{% else %}
No athletes.
{% endif %}
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Trying to start a service on boot on Android
...The other answers look good, but I thought I'd wrap everything up into one complete answer.
You need the following in your AndroidManifest.xml file:
In your <manifest> element:
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
In your <application> e...
R - Markdown avoiding package loading messages
...gh. When I source a file in an R-Chunk, the knitr output includes external comments as follows:
4 Answers
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WPF text Wrap vs WrapWithOverflow
...erlight. Only Wrap and NoWrap are supported in Silverlight. msdn.microsoft.com/en-us/library/…
– blachniet
Aug 26 '12 at 0:17
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Renaming or copying files and folder using NERDTree on Vim. Is it possible?
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Remove an Existing File from a Git Repo
...the file from the repo by executing "git rm --cached <file> and then committing this removal"
If you were also hoping to make the repo look as if it had never tracked that file, that is much more complicated and highly discouraged as it not only creates brand new commits for every single com...
Inherit from a generic base class, apply a constraint, and implement an interface in C#
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What's the false operator in C# good for?
... but if you override |, &, true and false in exactly the right way the compiler will call | and & when you write || and &&.
For example, look at this code (from http://ayende.com/blog/1574/nhibernate-criteria-api-operator-overloading - where I found out about this trick; archived ve...
Git: Ignore tracked files
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@haymansfield the help page for the command says the following Git will fail (gracefully) in case it needs to modify this file in the index e.g. when merging in a commit; thus, in case the assumed-untracked file is changed upstream, you will need to handle the ...