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Is it ever advantageous to use 'goto' in a language that supports loops and functions? If so, why?
...few reasons for using the "goto" statement that I'm aware of (some have spoken to this already):
Cleanly exiting a function
Often in a function, you may allocate resources and need to exit in multiple places. Programmers can simplify their code by putting the resource cleanup code at the end of t...
Is there a “do … while” loop in Ruby?
...condition> is rejected by Ruby's author Matz. Instead he suggests using Kernel#loop, e.g.
loop do
# some code here
break if <condition>
end
Here's an email exchange in 23 Nov 2005 where Matz states:
|> Don't use it please. I'm regretting this feature, and I'd like to
|> rem...
What's the cleanest way of applying map() to a dictionary in Swift?
I'd like to map a function on all keys in the dictionary. I was hoping something like the following would work, but filter cannot be applied to dictionary directly. What's the cleanest way of achieving this?
...
What is memoization and how can I use it in Python?
... the remembered result rather than computing the result again. You can think of it as a cache for method results. For further details, see page 387 for the definition in Introduction To Algorithms (3e), Cormen et al.
A simple example for computing factorials using memoization in Python would be som...
Mapping a function on the values of a map in Clojure
I want to transform one map of values to another map with the same keys but with a function applied to the values. I would think there was a function for doing this in the clojure api, but I have been unable to find it.
...
How to get the primary IP address of the local machine on Linux and OS X? [closed]
I am looking for a command line solution that would return me the primary (first) IP address of the localhost, other than 127.0.0.1
...
Is there a query language for JSON?
Is there a (roughly) SQL or XQuery-like language for querying JSON?
22 Answers
22
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Getting a list of associative array keys
...
You can use: Object.keys(obj)
Example:
var dictionary = {
"cats": [1, 2, 37, 38, 40, 32, 33, 35, 39, 36],
"dogs": [4, 5, 6, 3, 2]
};
// Get the keys
var keys = Object.keys(dictionary);
console.log(keys);
See reference below for b...
Cannot kill Python script with Ctrl-C
...ates the main thread, but because your threads aren't in daemon mode, they keep running, and that keeps the process alive. We can make them daemons:
f = FirstThread()
f.daemon = True
f.start()
s = SecondThread()
s.daemon = True
s.start()
But then there's another problem - once the main thread has...
How do I calculate square root in Python?
...
Merlin
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answered Mar 7 '12 at 2:50
smessingsmessing...