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What does the `forall` keyword in Haskell/GHC do?
...here
val :: b
val = maybe onNothin onJust mval
This code doesn't compile (syntax error) in plain Haskell 98. It requires an extension to support the forall keyword.
Basically, there are 3 different common uses for the forall keyword (or at least so it seems), and each has its own ...
How to install packages offline?
What's the best way to download a python package and it's dependencies from pypi for offline installation on another machine? Is there any easy way to do this with pip or easy_install? I'm trying to install the requests library on a FreeBSD box that is not connected to the internet.
...
How to check if a python module exists without importing it
...le('eggs')
found = True
except ImportError:
found = False
To find dotted imports, you need to do more:
import imp
try:
spam_info = imp.find_module('spam')
spam = imp.load_module('spam', *spam_info)
imp.find_module('eggs', spam.__path__) # __path__ is already a list
found = T...
How do I get the path of a process in Unix / Linux
In Windows environment there is an API to obtain the path which is running a process. Is there something similar in Unix / Linux?
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jQuery Determine if a matched class has a given id
...a string selector:
$(".bar:first").is("#foo"); // TRUE if first '.bar' in document is also '#foo'
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How to place the ~/.composer/vendor/bin directory in your PATH?
...ssages everything I try. I'm now trying the first method in the quickstart documentation, that is, via Laravel Installer, but it says to "Make sure to place the ~/.composer/vendor/bin directory in your PATH so the Laravel executable is found when you run the Laravel command in your terminal." so...
Difference between System.DateTime.Now and System.DateTime.Today
...ateTimeKind.Local - which could lead to other errors depending on what you do with it.
So, the simple answer is that DateTime.Today is equivalent to DateTime.Now.Date.
But IMHO - You shouldn't use either one of these, or any of the above equivalents.
When you ask for DateTime.Now, you are asking f...
Loop through properties in JavaScript object with Lodash
....forOwn().
_.forOwn(obj, function(value, key) { } );
https://lodash.com/docs#forOwn
Note that forOwn checks hasOwnProperty, as you usually need to do when looping over an object's properties. forIn does not do this check.
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Is std::vector so much slower than plain arrays?
I've always thought it's the general wisdom that std::vector is "implemented as an array," blah blah blah. Today I went down and tested it, and it seems to be not so:
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How to get root access on Android emulator?
...o 2.3.3), and I tried many methods for getting root in Android emulator. I don't use any Android device and test everything on emulator(AVD).
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