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What does the “Just” syntax mean in Haskell?
I have scoured the internet for an actual explanation of what this keyword does. Every Haskell tutorial that I have looked at just starts using it randomly and never explains what it does (and I've looked at many).
...
Why JavaScript rather than a standard browser virtual machine?
...use of bad timing and technical stupidities which are mostly resolved. Allowing any language between the script tag (with restrictions) would be pretty cool, and certainly not impossible nor unpractical.
– Gerbrand
Dec 18 '10 at 13:55
...
How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
... preferred whenever practical.
In this case, you typically follow the following process:
CREATE a TEMPORARY table
COPY or bulk-insert the new data into the temp table
LOCK the target table IN EXCLUSIVE MODE. This permits other transactions to SELECT, but not make any changes to the table.
Do an ...
Embedding unmanaged dll into a managed C# dll
... if (h == IntPtr.Zero)
{
Exception e = new Win32Exception();
throw new DllNotFoundException("Unable to load library: " + dllName + " from " + tempFolder, e);
}
}
}
}
...
How does BLAS get such extreme performance?
...t all).
IMHO no BLAS implementation uses algorithms like the Coppersmith–Winograd algorithm or the Strassen algorithm. The likely reasons are:
Maybe its not possible to provide a cache optimized implementation of these algorithms (i.e. you would loose more then you would win)
These algorithms a...
Dictionary vs Object - which is more efficient and why?
...ots=3sec obj=11sec dict=12sec namedtuple=16sec. I'm using CPython 2.6.6 on Win7 64bit
– Jonathan
Jul 5 '11 at 13:24
To...
What's the difference between utf8_general_ci and utf8_unicode_ci?
...al_ci and utf8_unicode_ci, but I did not find any benchmarks listed on the internet, so I decided to create benchmarks myself.
I created a very simple table with 500,000 rows:
CREATE TABLE test(
ID INT(11) DEFAULT NULL,
Description VARCHAR(20) DEFAULT NULL
)
ENGINE = INNODB
CHARACTER SET utf8
...
Retrieve specific commit from a remote Git repository
...ey are fed to us by the config machinery, as that lets our usual "last one wins" config precedence work (and entries in .git/config, for example, will override /etc/gitconfig).
So you can now do:
git config --system transfer.hideRefs refs/secret
git config transfer.hideRefs '!refs/secret/not-...
private final static attribute vs private final attribute
... reason to have an inline declaration initializing the value like the following, as each instance will have its own NUMBER but always with the same value (is immutable and initialized with a literal). This is the same than to have only one final static variable for all instances.
private final int ...
How do I expire a PHP session after 30 minutes?
... session handler, your filesystem must keep track of access times (atime). Windows FAT does not so you will have to come up with another way to handle garbage collecting your session if you are stuck with a FAT filesystem or any other filesystem where atime tracking is not available. Since PHP 4.2.3...