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How to check if a variable exists in a FreeMarker template?
...ter fit:
<#if userName?has_content>
... do something
</#if>
http://freemarker.sourceforge.net/docs/ref_builtins_expert.html
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follo...
Regex lookahead, lookbehind and atomic groups
...n succeed as s immediately follows in foots, and stop.
Some resources
http://www.regular-expressions.info/lookaround.html
http://www.rexegg.com/regex-lookarounds.html
Online testers
https://regex101.com
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Django: “projects” vs “apps”
...ollowing blog posts very useful about django applications and projects:
http://www.b-list.org/weblog/2006/sep/10/django-tips-laying-out-application/
http://web.archive.org/web/20080302205555/www.pointy-stick.com/blog/2007/11/09/django-tip-developing-without-projects/
In principle, you have a lo...
What is the fastest way to get the value of π?
...way (more universal solution) is:
look up Pi on the Internet, e.g. here:
http://www.eveandersson.com/pi/digits/1000000 (1 million digits .. what's your floating point precision? )
or here:
http://3.141592653589793238462643383279502884197169399375105820974944592.com/
or here:
http://en.wikiped...
What is Android keystore file, and what is it used for?
...ion about the signing process on the official Android documentation here : http://developer.android.com/guide/publishing/app-signing.html
Yes, you can sign several applications with the same keystore. But you must remember one important thing : if you publish an app on the Play Store, you have to s...
To draw an Underline below the TextView in Android
...reate a drawable (hyperlink_underline.xml):
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<item android:top="-10dp"
android:left="-10dp"
android:right="-10dp">
<shape android:shape="rectangle">
<solid android:color="@android...
How to delete a word and go into insert mode in Vim?
...ter, try: "change inner { block" and "change a { block".
Documentation at http://vimdoc.sourceforge.net/htmldoc/motion.html#text-objects
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follow...
Pandas dataframe get first row of each group
...nth(0) is the same as first()):
df.groupby('id').nth(1)
Documentation: http://pandas.pydata.org/pandas-docs/stable/groupby.html#taking-the-nth-row-of-each-group
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Using Transactions or SaveChanges(false) and AcceptAllChanges()?
...F6 (Entity Framework 6+), this has changed for database calls to SQL.
See: http://msdn.microsoft.com/en-us/data/dn456843.aspx
use context.Database.BeginTransaction.
From MSDN:
using (var context = new BloggingContext())
{
using (var dbContextTransaction = context.Database.BeginTransaction(...
When is the thread pool used?
...nchronous I/O is not always a thread pool, specifically in the case of the http module a different strategy appears to be used at this time. For our purposes here it's mainly important to note how the asynchronous context is achieved (by using libuv) and that the thread pool maintained by libuv is o...