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How does deriving work in Haskell?
Algebraic Data Types (ADTs) in Haskell can automatically become instances of some typeclasse s (like Show , Eq ) by deriving from them.
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What is the difference between a mutable and immutable string in C#?
...pe
To "effect a change" on a string represented as a C# String, you actually create a new String object. The original String is not changed ... because it is unchangeable.
In most cases it is better to use String because it is easier reason about them; e.g. you don't need to consider the possib...
Synchronous request in Node.js
If I need to call 3 http API in sequential order, what would be a better alternative to the following code:
18 Answers
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How can I get the version defined in setup.py (setuptools) in my package?
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Interrogate version string of already-installed distribution
To retrieve the version from inside your package at runtime (what your question appears to actually be asking), you can use:
import pkg_resources # part of setuptools
version = pkg_resources.require("MyP...
What is a “callable”?
...t's clear what a metaclass is , there is an associated concept that I use all the time without knowing what it really means.
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Are types like uint32, int32, uint64, int64 defined in any stdlib header?
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This answer is wrong. All of the above are only available if an exact width type of that size (no padding) exists in the implementation. Even if not, however, the types int_leastNN_t and uint_leastNN_t for NN 8, 16, 32, and 64 must always exist. C...
What is the purpose of class methods?
...sson was that Python is not Java , and so I've just spent a while turning all my Class methods into functions.
17 Answers
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Python module for converting PDF to text [closed]
... updated again in version 20100213
You can check the version you have installed with the following:
>>> import pdfminer
>>> pdfminer.__version__
'20100213'
Here's the updated version (with comments on what I changed/added):
def pdf_to_csv(filename):
from cStringIO import S...
Is there a REAL performance difference between INT and VARCHAR primary keys?
... and a coworker won't budge on the INT AUTO_INCREMENT as a primary key for all tables.
14 Answers
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How do I add multiple arguments to my custom template filter in a django template?
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It is possible and fairly simple.
Django only allows one argument to your filter, but there's no reason you can't put all your arguments into a single string using a comma to separate them.
So for example, if you want a filter that checks if variable X is in the list [1...