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When should I use nil and NULL in Objective-C?
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technically, they are exactly equal, you can send messages to both nil and to NULL. Idiomatically though nil is usually used to represent an object
– cobbal
Oct 14 '09 at 5:43
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Why can't I use a list as a dict key in python?
..., with the hash as, say, their memory location?
It can be done without really breaking any of the requirements, but it leads to unexpected behavior. Lists are generally treated as if their value was derived from their content's values, for instance when checking (in-)equality. Many would - underst...
Any reason not to use '+' to concatenate two strings?
... Tuple would be faster - the code was just an example :) Usually long multiple string inputs are dynamic.
– Mikko Ohtamaa
Apr 6 '12 at 12:52
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Practical usage of setjmp and longjmp in C
...n me where exactly setjmp() and longjmp() functions can be used practically in embedded programming? I know that these are for error handling. But I'd like to know some use cases.
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How to find all links / pages on a website
Is it possible to find all the pages and links on ANY given website? I'd like to enter a URL and produce a directory tree of all links from that site?
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How do I turn off PHP Notices?
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@user try a phpinfo() to see whether the setting actually applies. Forgive me, but I strongly doubt that you have found a bug in PHP 5.3 - I will only believe it when I see it :)
– Pekka
May 20 '10 at 11:36
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curl : (1) Protocol https not supported or disabled in libcurl
...r HERE for windows,
it says there that:
curl -XPUT 'http://localhost:9200/api/twittervnext/tweet'
Woops, first try and already an error:
curl: (1) Protocol 'http not supported or disabled in libcurl
The reason for this error is kind of stupid, Windows doesn’t like it when you are using singl...
Composite Key with EF 4.1 Code First
...tyID and ActivityName properties with Key annotation or you can use fluent API as described by @taylonr.
Edit:
This should work - composite key defined with annotations requires explicit column order:
public class ActivityType
{
[Key, Column(Order = 0)]
public int ActivityID { get; set; }...
Where is my Django installation?
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Current top (accepted) answer works with my Ubuntu installation. As does yours. As do all of them!
– Adam Marshall
Apr 28 '14 at 14:24
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What is the common header format of Python files?
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Its all metadata for the Foobar module.
The first one is the docstring of the module, that is already explained in Peter's answer.
How do I organize my modules (source files)? (Archive)
The first line of each file shoud be #!/us...