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Difference between single and double quotes in Bash
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Single quotes won't interpolate anything, but double quotes will. For example: variables, backticks, certain \ escapes, etc.
Example:
$ echo "$(echo "upg")"
upg
$ echo '$(echo "upg")'
$(echo "upg")
The Bash manual has this to say:
3.1.2.2 Single Quotes
Enclosing characters in single...
How can I view all the git repositories on my machine?
...ries don't need to be named name.git thats just a convention, that I for example, don't follow.
– Arkaitz Jimenez
Jan 7 '10 at 14:09
3
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Why doesn't ruby support method overloading?
...; end; # second argument has a default value
method(10)
# Now the method call can match the first one as well as the second one,
# so here is the problem.
So ruby needs to maintain one method in the method look up chain with a unique name.
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How does “cat
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This is called heredoc format to provide a string into stdin. See https://en.wikipedia.org/wiki/Here_document#Unix_shells for more details.
From man bash:
Here Documents
This type of redirection instructs the shell to read...
Find first element in a sequence that matches a predicate
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@geekazoid: seq.find(&method(:predicate)) or even more concise for instance methods e.g.: [1,1,4].find(&:even?)
– jfs
Jul 20 '15 at 5:07
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Difference between abstract class and interface in Python
...s to define and enforce an interface.
Using an Abstract Base Class
For example, say we want to use one of the abstract base classes from the collections module:
import collections
class MySet(collections.Set):
pass
If we try to use it, we get an TypeError because the class we created does n...
What's the difference between django OneToOneField and ForeignKey?
..."reverse" relation, a ForeignKey "reverse" relation returns a QuerySet.
Example
For example, if we have the following two models (full model code below):
Car model uses OneToOneField(Engine)
Car2 model uses ForeignKey(Engine2, unique=True)
From within python manage.py shell execute the followi...
How do you run a Python script as a service in Windows?
... You give special mention to pythoncom, and you import it in your example code. The problem is you never actually use pythoncom anywhere in your example code, you only import it. Why give it special mention and then not show its usage?
– Buttons840
Apr...
Git Tag list, display commit sha1 hashes
...t'll show the hash of the tag object itself.
– Lily Ballard
Jan 9 '12 at 23:43
20
To show a list ...
How do I create an average from a Ruby array?
...inject interface, mentioned in the documentation. The to_proc operator is &.
– Chuck
Aug 27 '09 at 18:53
21
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