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How to check if an object is a list or tuple (but not string)?
... doing there? That's kind of a hack. But it is essential.
This function calls itself recursively on anything that acts like a list. If we didn't handle the string specially, then it would be treated like a list, and split up one character at a time. But then the recursive call would try to trea...
What is a covariant return type?
...ridden method in MyFoo would have to be declared to return Object - and so calling code would have to explicitly downcast the result of the method call (even thought both sides "know" it can only ever be an instance of MyFoo).
Note that there's nothing special about clone() and that any overridden ...
How to execute a Ruby script in Terminal?
...
Just call: ruby your_program.rb
or
start your program with #!/usr/bin/env ruby,
make your file executable by running chmod +x your_program.rb
and do ./your_program.rb some_param
...
How to get the path of a running JAR file?
...
One more note: While calling this function from the Jar, the name of the jar is appended at the end for me, therefore had to execute: path.substring(0, path.lastIndexOf("/") + 1);
– will824
Oct 5 '11 at 15:2...
How to sort a list of strings?
What is the best way of creating an alphabetically sorted list in Python?
11 Answers
1...
Skip List vs. Binary Search Tree
...rithms'' [ps.gz].
One of the more recent improvements on these is the so-called chromatic tree (basically you have some weight such that black would be 1 and red would be zero, but you also allow values in between). And how does a chromatic tree fare against skip list? Let's see what Brown et al. ...
What's the best way to parse command line arguments? [closed]
...t will accept -q or --query as options, store the argument in an attribute called query and has a default value if you don't specify it. It is also self-documenting in that you declare the help argument (which will be used when run with -h/--help) right there with the option.
Usually you parse you...
Print all properties of a Python Class [duplicate]
...
Another way is to call the dir() function (see https://docs.python.org/2/library/functions.html#dir).
a = Animal()
dir(a)
>>>
['__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__getattribute__',
'__hash__', '__in...
Checking network connection
...ot have a working internet connection, the DNS lookup itself may block the call to urllib_request.urlopen for more than a second. Thanks to @rzetterberg for pointing this out.
If the fixed IP address above is not working, you can find a current IP address for google.com (on unix) by running
% di...
What database does Google use?
...ands of machines
it is easy to add more machines to the system and automatically start taking advantage of those resources without any reconfiguration
each table has multiple dimensions (one of which is a field for time, allowing versioning)
tables are optimized for GFS (Google File System) by being...