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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
... can be used to detect if a variable has been already initialized. Additionally and more ideal is the solution of empty() since it does not generate a warning or error message if the variable is not initialized.
From PHP documentation:
No warning is generated if the variable does not exist. T...
How can I manually generate a .pyc file from a .py file
...n not depend on Python's "import" statement to generate .pyc file automatically
8 Answers
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CryptographicException 'Keyset does not exist', but only through WCF
I have some code that makes a call to a third party web service that is secured using X.509 certification.
18 Answers
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The purpose of Model View Projection Matrix
...d space to camera space, projection from camera to screen.
If you compose all three, you can use the one result to map all the way from object space to screen space, making you able to work out what you need to pass on to the next stage of a programmable pipeline from the incoming vertex positions....
How to delete files/subfolders in a specific directory at the command prompt in Windows
Say, there is a variable called %pathtofolder% , as it makes it clear it is a full path of a folder.
15 Answers
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What are the differences between local branch, local tracking branch, remote branch and remote track
I just started using Git and I got really confused between different branches. Can anyone help me to figure out what the following branch types are?
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Why is lazy evaluation useful?
...epending on the sequence of conditional expressions, only a subset may actually be used. In a language like C, all three values would be computed anyway; but in Haskell, only the necessary values are computed.
It also allows for cool stuff like infinite lists. I can't have an infinite list in a lan...
Could not load file or assembly 'System.Web.Http 4.0.0 after update from 2012 to 2013
...
I fixed this by reinstalling the NuGet package, which corrects broken dependencies. From the package manager, run:
Update-Package Microsoft.AspNet.WebApi -reinstall
shar...
Should we use Nexus or Artifactory for a Maven Repo?
...out Artifactory but here are my reasons for using Nexus:
Dead simple install (and since 1.2, dead simple upgrade, too)
Very good web UI
Easy to maintain, almost no administrative overhead
Provides you with RSS feeds of recently installed, broken artifacts and errors
It can group several repositori...
EF Code First foreign key without navigation property
...class and sql is just the above SQL command as string.
Be aware that with all this EF has no clue that ParentId is a foreign key that describes a relationship. EF will consider it only as an ordinary scalar property. Somehow all the above is only a more complicated and slower way compared to just o...