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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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Converting Java objects to JSON with Jackson
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object MUST have getters for all fields, wich you want your JSON includes.
– Drakonoved
Sep 25 '17 at 15:42
add a comment
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MPICH vs OpenMPI
...xtensive optimizations that make it the preferred implementation in nearly all cases.
Feature Support from the Latest MPI Standard
An orthogonal axis to hardware/platform support is coverage of the MPI standard. Here MPICH is usually far and away superior. MPICH has been the first implementation...
Changing java platform on which netbeans runs
I am using Netbeans 6.7. I had first installed Java 1.5 before installing Netbeans. When i installed Netbeans it took Java 1.5 as the default version. Then i installed Java 1.6 on my machine. I need to change the default JDK of my netbeans to 1.6 not only to a specific project but to the whole Netbe...
server certificate verification failed. CAfile: /etc/ssl/certs/ca-certificates.crt CRLfile: none
...b certificate used for your gitLab server, and add it to your </git_installation_folder>/bin/curl-ca-bundle.crt.
To check if at least the clone works without checking said certificate, you can set:
export GIT_SSL_NO_VERIFY=1
#or
git config --global http.sslverify false
But that would be fo...
django.core.exceptions.ImproperlyConfigured: Error loading MySQLdb module: No module named MySQLdb
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Ron ERon E
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How do I check if the Java JDK is installed on Mac?
How do you check if Java SDK is installed on a Mac?
8 Answers
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How to check if a process id (PID) exists
...process is not owned by the running user, you may not have permissions to call kill -0. Better to use ps -p $PID > /dev/null 2>&1, which allows you to see process status, even if you do not have permissions to send a signal.
– mckoss
Apr 1 '12 at 16:...
Is there an expression for an infinite generator?
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for x in iter(int, 1): pass
Two-argument iter = zero-argument callable + sentinel value
int() always returns 0
Therefore, iter(int, 1) is an infinite iterator. There are obviously a huge number of variations on this particular theme (especially once you add lambda into the mix). One va...
How can I detect if the user is on localhost in PHP?
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Which would make this actually easier to break than spoofing the IP. You should really change it.
– Pekka
Jan 13 '10 at 0:09
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