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Why does my 'git branch' have no master?
... I keep reading about a "master" branch. Is "master" just a conventional name that people used or does it have special meaning like HEAD ?
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MySQL: selecting rows where a column is null
...here bar <> "abc" will not return rows where bar is null. That threw me for a loop today. The docs call <> the "not equal to" operator, but really it's the "is equal to something other than" operator.
– StackOverthrow
May 24 '18 at 1:23
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Why do Python's math.ceil() and math.floor() operations return floats instead of integers?
Can someone explain this (straight from the docs - emphasis mine):
8 Answers
8
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Compare two files line by line and generate the difference in another file
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diff(1) is not the answer, but comm(1) is.
NAME
comm - compare two sorted files line by line
SYNOPSIS
comm [OPTION]... FILE1 FILE2
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-1 suppress lines unique to FILE1
-2 suppress lines unique to FILE2
-3 suppress lin...
getting type T from IEnumerable
is there a way to retrieve type T from IEnumerable<T> through reflection?
13 Answers
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jQuery/JavaScript: accessing contents of an iframe
I would like to manipulate the HTML inside an iframe using jQuery.
14 Answers
14
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Relationship between hashCode and equals method in Java [duplicate]
I read in many places saying while override equals method in Java, should override hashCode method too, otherwise it is "violating the contract".
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Can we omit parentheses when creating an object using the “new” operator?
... the grammar by allowing the parenthesis to be omitted if there are no arguments in the function call. Here are some examples using the new operator:
o = new Object; // Optional parenthesis omitted here
d = new Date();
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Personally, I always use the parenthesis, even when the constructor tak...
Choosing a file in Python with simple Dialog
...inter import Tk for Python 3.x
from tkinter.filedialog import askopenfilename
Tk().withdraw() # we don't want a full GUI, so keep the root window from appearing
filename = askopenfilename() # show an "Open" dialog box and return the path to the selected file
print(filename)
Done!
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What is /dev/null 2>&1?
...hich discards it.
(The >> seems sort of superfluous, since >> means append while > means truncate and write, and either appending to or writing to /dev/null has the same net effect. I usually just use > for that reason.)
2>&1 redirects standard error (2) to standard output...