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Does Haskell require a garbage collector?
...grams, the lifetime of an object can only be determined at runtime.
For example, consider the following program:
main = loop (Just [1..1000]) where
loop :: Maybe [Int] -> IO ()
loop obj = do
print obj
resp <- getLine
if resp == "clear"
then loop Nothing
else loop o...
Java Name Hiding: The Hard Way
I have a problem with name hiding that is extremely hard to solve. Here is a simplified version that explains the problem:
...
What is the difference between a string and a byte string?
...t encoding may map the same bytes to a different string:
>>> b'\xcf\x84o\xcf\x81\xce\xbdo\xcf\x82'.decode('utf-16')
'蓏콯캁澽苏'
>>> b'\xcf\x84o\xcf\x81\xce\xbdo\xcf\x82'.decode('utf-8')
'τoρνoς'
Once you know which one to use, you can use the .decode() method of the b...
Opposite of %in%: exclude rows with values specified in a vector
...presented by the letters from A to Z. I want to create a subset D2, which excludes some values, say, B, N and T. Basically, I want a command which is the opposite of %in%
...
What exactly does an #if 0 … #endif block do?
...
Not only does it not get executed, it doesn't even get compiled.
#if is a preprocessor command, which gets evaluated before the actual compilation step. The code inside that block doesn't appear in the compiled binary.
It's often used for temporaril...
How do I get the row count of a pandas DataFrame?
...
You can use the .shape property or just len(DataFrame.index). However, there are notable performance differences ( len(DataFrame.index) is fastest).
Code to reproduce the plot:
import numpy as np
import pandas as pd
import perfplot
perfplot.save(
"out.png",
setup=lambda ...
“Variable” variables in Javascript?
I know it's possible in PHP to have "variable" variables. For example
7 Answers
7
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How to invoke the super constructor in Python?
...structor is invoked implicitly. How does one invoke it in Python? I would expect super(self) but this doesn't work.
7 Ans...
ImportError: Cannot import name X
...ld know that two classes should NEVER be dependant on each other. This is extremely important in C++, and even if it's not the #1 thing in Python, it's still a really good idea to follow this rule. Never have two classes which know each other, ever. If you need help with creating the structure for y...
How to print (using cout) a number in binary form?
...about operating systems and we're learning how to convert from binary to hexadecimal, decimal to hexadecimal, etc. and today we just learned how signed/unsigned numbers are stored in memory using the two's complement (~number + 1).
...