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Finding the source code for built-in Python functions?
Is there a way to see how built in functions work in python? I don't mean just how to use them, but also how were they built, what is the code behind sorted or enumerate etc...?
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Can I find out the return value before returning while debugging in Visual Studio?
Take the following function:
20 Answers
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Get int value from enum in C#
...ral). In this class there is an enum called Question (singular) which looks like this.
28 Answers
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Opposite of %in%: exclude rows with values specified in a vector
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You can use the ! operator to basically make any TRUE FALSE and every FALSE TRUE. so:
D2 = subset(D1, !(V1 %in% c('B','N','T')))
EDIT:
You can also make an operator yourself:
'%!in%' <- function(x,y)!('%in%'(x,y))
c(1,3,11)%!in%1:10
[1] FALSE FALSE TRUE
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Is there any way to delete local commits in Mercurial?
So I keep making a silly mistake in Mercurial. Often times, I'll start work without doing an "hg pull" and an "hg update." When I try to push my changes, I get an error.
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How can I check for Python version in a program that uses new language features?
... control early enough, you could split it into different .py files and check compatibility in the main file before importing (e.g. in __init__.py in a package):
# __init__.py
# Check compatibility
try:
eval("1 if True else 2")
except SyntaxError:
raise ImportError("requires ternary support")
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How do you mock out the file system in C# for unit testing?
Are there any libraries or methods to mock out the file system in C# to write unit tests? In my current case I have methods that check whether certain file exists and read the creation date. I may need more than that in future.
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Why use multiple columns as primary keys (composite primary key)
This example is taken from w3schools .
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9
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Does “\d” in regex mean a digit?
...d 3 but not 2 . I was wondering if \d matches a digit satisfying what kind of requirement? I am talking about Python style regex.
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