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Why is there “data” and “newtype” in Haskell? [duplicate]
...peek inside.
Couldn't the compiler handle this for itself.
No, not really—this is a case where as the programmer you get to decide whether the constructor is strict or lazy. To understand when and how to make constructors strict or lazy, you have to have a much better understanding of lazy ...
Counting the Number of keywords in a dictionary in python
... the len() function.
> a = {'foo':42, 'bar':69}
> len(a)
2
To get all the distinct words (i.e. the keys), use the .keys() method.
> list(a.keys())
['foo', 'bar']
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Inherit docstrings in Python class inheritance
...out this a while ago, and a recipe was created. Check it out here.
"""
doc_inherit decorator
Usage:
class Foo(object):
def foo(self):
"Frobber"
pass
class Bar(Foo):
@doc_inherit
def foo(self):
pass
Now, Bar.foo.__doc__ == Bar().foo.__doc__ == Foo.foo.__doc__...
Matplotlib (pyplot) savefig outputs blank image
...values that depend whether or not T0 exists.
Second, after plt.show() is called, a new figure is created. To deal with this, you can
Call plt.savefig('tessstttyyy.png', dpi=100) before you call plt.show()
Save the figure before you show() by calling plt.gcf() for "get current figure", then you ca...
How do you split and unsplit a window/view in Eclipse IDE?
...tcut for splitting is:
Azerty keyboard:
Ctrl + _ for split horizontally, and
Ctrl + { for split vertically.
Qwerty US keyboard:
Ctrl + Shift + - (accessing _) for split horizontally, and
Ctrl + Shift + [ (accessing {) for split vertically.
MacOS - Qwerty US keyboard:
...
Publish to S3 using Git?
...we wanted). Next create an S3 bucket to store your repository in, let’s call it git-repos, and then create a git repository to upload:
s3cmd mb s3://git-repos
mkdir chef-recipes
cd chef-recipes
git init
touch README
git add README
git commit README
git remote add origin amazon-s3://.jgit@git-repo...
How do you design object oriented projects? [closed]
.... If you're a Java developer, NetBeans 6.7 from Sun has a UML module that allows for diagramming as well as round-trip engineering and it's FREE. Eclipse (an open source Java IDE), also has a modeling framework, but I have no experience with it. You may also want to try out ArgoUML, an open sour...
How to get the parent dir location
...bspath doesn't validate anything, so if we're already appending strings to __file__ there's no need to bother with dirname or joining or any of that. Just treat __file__ as a directory and start climbing:
# climb to __file__'s parent's parent:
os.path.abspath(__file__ + "/../../")
That's far less...
Why and not taking font-family and font-size from body?
...
All browsers have built-in default stylesheets. That's why, when you make a page without any styles defined at all, <h1> tags are large and bold, and <strong> makes text bold. Similarly, the font styles for <in...
Capture characters from standard input without waiting for enter to be pressed
...oo much on the terminal used that may be connected with stdin (they are usually line buffered). You can, however use a library for that:
conio available with Windows compilers. Use the _getch() function to give you a character without waiting for the Enter key. I'm not a frequent Windows developer...