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How to check if an NSDictionary or NSMutableDictionary contains a key?
I need to check if an dict has a key or not. How?
15 Answers
15
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How to design a database for User Defined Fields?
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If performance is the primary concern, I would go with #6... a table per UDF (really, this is a variant of #2). This answer is specifically tailored to this situation and the description of the data distribution and access patterns ...
What is a Maven artifact?
...An artifact is a file, usually a JAR, that gets deployed to a Maven repository.
A Maven build produces one or more artifacts, such as a compiled JAR and a "sources" JAR.
Each artifact has a group ID (usually a reversed domain name, like com.example.foo), an artifact ID (just a name), and a version...
How to retrieve a user environment variable in CMake (Windows)
I know how to retrieve a normal machine wide environment variable in CMAKE using
4 Answers
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How to call one shell script from another shell script?
... the file is to the $PATH environment variable. Then you can call it as a normal command;
Or call it with the source command (alias is .) like this: source /path/to/script;
Or use the bash command to execute it: /bin/bash /path/to/script;
The first and third methods execute the script as another p...
Hex representation of a color with alpha channel?
Is there a W3 or any other noteworthy standard on how to represent a color (including alpha channel) in hex format?
5 Answe...
Make sure only a single instance of a program is running
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The following code should do the job, it is cross-platform and runs on Python 2.4-3.2. I tested it on Windows, OS X and Linux.
from tendo import singleton
me = singleton.SingleInstance() # will sys.exit(-1) if other instance is running
The latest code version is available sing...
Limit ggplot2 axes without removing data (outside limits): zoom
...cify axis limits in ggplot the outlying points are removed. This is fine for points, but you might want to plot lines that intersect with the specified range, but ggplot's range or xlim/ylim methods removes these. Is there another way to specify the plot axis range without removing outlying da...
jQuery returning “parsererror” for ajax request
Been getting a "parsererror" from jquery for an Ajax request, I have tried changing the POST to a GET, returning the data in a few different ways (creating classes, etc.) but I cant seem to figure out what the problem is.
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What is the difference between 0.0.0.0, 127.0.0.1 and localhost?
...nd to this address by default. I can still visit it via http://localhost:port . But for Jekyll , it seems that the default setting (e.g. 0.0.0.0:4000) requires Internet access. I cannot run Jekyll server without Internet. Is it a small bug?
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