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How to check if command line tools is installed
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32
To check if command line tools are installed run:
xcode-select --version
// if installed you ...
Python None comparison: should I use “is” or ==?
My editor warns me when I compare my_var == None , but no warning when I use my_var is None .
3 Answers
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Why does the indexing start with zero in 'C'?
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answered Sep 6 '11 at 13:32
Doug T.Doug T.
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Unable to install Maven on Windows: “JAVA_HOME is set to an invalid directory”
...e-maven-2.2.0\bin" is on your command search path.
Make sure that the JAVA_HOME variable refers to the home directory for your Java installation. If you are executing Java from "E:\Sun\SDK\jdk\bin", then the JAVA_HOME variable needs to point to "E:\Sun\SDK\jdk".
NB: JAVA_HOME should NOT end with "...
How to 'insert if not exists' in MySQL?
I started by googling, and found this article which talks about mutex tables.
10 Answers
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Passing a list of kwargs?
...eterPeter
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What is the definition of “interface” in object oriented programming
...dom.randint(0,10)
# What you care about
class SecretGame(object):
def __init__(self, number_generator):
number = number_generator.generate()
print number
Here, none of the classes implement an interface. Python does not care about that, because the SecretGame class will just t...
Sort hash by key, return hash in Ruby
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In Ruby 2.1 it is simple:
h.sort.to_h
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How to programmatically determine the current checked out Git branch [duplicate]
...ments? :-D
– conny
Jun 23 '10 at 16:32
52
@conny git symbolic-ref HEAD 2>/dev/null | cut -d"/"...
variable === undefined vs. typeof variable === “undefined”
The jQuery Core Style Guidelines suggest two different ways to check whether a variable is defined.
8 Answers
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