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How does deriving work in Haskell?
...-). This is to say that automatic deriving is baked into the Haskell spec, and every compiler can choose to implement it in its own way. There's lots of work on how to make it extensible however.
Derive is a tool for Haskell to let you write your own deriving mechanisms.
GHC used to provide a deri...
AI2 Keep Awake
...t WakeLocks if you do not really need them, use them as rarely as possible and release them as soon as possible. If actions are to be performed only occasionally, it is not necessary for the CPU to be constantly active. Instead, an alarm can be used (see UrsAI2Alarm ). Motivation For so...
Is UML practical? [closed]
In college I've had numerous design and UML oriented courses, and I recognize that UML can be used to benefit a software project, especially use-case mapping, but is it really practical? I've done a few co-op work terms, and it appears that UML is not used heavily in the industry. Is it worth ...
Why number 9 in kill -9 command in unix? [closed]
I understand it's off topic, I couldn't find anywhere online and I was thinking maybe programming gurus in the community might know this.
I usually use
...
PHPMyAdmin Default login password [closed]
I have done a fresh installation of Fedora 14 and installed the phpMyAdmin module. When I run phpMyAdmin, it asks me for a username and password.
...
A hex viewer / editor plugin for Notepad++? [closed]
...had a look through the plugins as well as searched the forum for Notepad++ and have not seen a solution to editing data as hex in Notepad++ .
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How do I delete an exported environment variable?
...
unset is the command you're looking for.
unset GNUPLOT_DRIVER_DIR
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Delete/Reset all entries in Core Data?
...ly.
The programmatic way for iterating through each entity is both slower and prone to error. The use for doing it that way is if you want to delete some entities and not others. However you still need to make sure you retain referential integrity or you won't be able to persist your changes.
Ju...
Concatenating Files And Insert New Line In Between Files
...ke sure the file finalfile.txt does not exist before you run the above command.
If you are allowed to use awk you can do:
awk 'FNR==1{print ""}1' *.txt > finalfile.txt
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What is the proper way to check if a string is empty in Perl?
... comparisons in Perl, use eq or ne:
if ($str eq "")
{
// ...
}
The == and != operators are numeric comparison operators. They will attempt to convert both operands to integers before comparing them.
See the perlop man page for more information.
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