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Learning Python from Ruby; Differences and Similarities
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[x*x for x in values if x > 15]
to get a new list of the squares of all values greater than 15. In Ruby, you'd have to write the following:
values.select {|v| v > 15}.map {|v| v * v}
The Ruby code doesn't feel as compact. It's also not as efficient since it first converts the values a...
Virtual Memory Usage from Java under Linux, too much memory used
... a long-standing complaint with Java, but it's largely meaningless, and usually based on looking at the wrong information. The usual phrasing is something like "Hello World on Java takes 10 megabytes! Why does it need that?" Well, here's a way to make Hello World on a 64-bit JVM claim to take over 4...
How to print a int64_t type in C
... hexadecimal.
cppreference.com has a full listing of available macros for all types including intptr_t (PRIxPTR). There are separate macros for scanf, like SCNd64.
A typical definition of PRIu16 would be "hu", so implicit string-constant concatenation happens at compile time.
For your code to ...
How do I check if the Java JDK is installed on Mac?
How do you check if Java SDK is installed on a Mac?
8 Answers
8
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Show the progress of a Python multiprocessing pool imap_unordered call?
...fully doing a multiprocessing Pool set of tasks with a imap_unordered() call:
9 Answers
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Debugging in Clojure? [closed]
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There's also dotrace, which allows you to look at the inputs and outputs of selected functions.
(use 'clojure.contrib.trace)
(defn fib[n] (if (< n 2) n (+ (fib (- n 1)) (fib (- n 2)))))
(dotrace [fib] (fib 3))
produces the output:
TRACE t4425: (f...
Adding a Method to an Existing Object Instance
...that instance will be passed as the first argument whenever the method is called.
Callables that are attributes of a class (as opposed to an instance) are still unbound, though, so you can modify the class definition whenever you want:
>>> def fooFighters( self ):
... print "fooFighters...
Why use Abstract Base Classes in Python?
...emented classes.
Long version
There is a contract between a class and its callers. The class promises to do certain things and have certain properties.
There are different levels to the contract.
At a very low level, the contract might include the name of a method or its number of parameters.
In a s...
What are rvalues, lvalues, xvalues, glvalues, and prvalues?
...e they needed? Probably not if we wish to forfeit the new features. But to allow better optimization we should probably embrace them.
Quoting n3055:
An lvalue (so-called, historically,
because lvalues could appear on the
left-hand side of an assignment
expression) designates a function or
an obj...
How to convert an xml string to a dictionary?
... first two tags
# in a series are different, then they are all different.
if len(element) == 1 or element[0].tag != element[1].tag:
aDict = XmlDictConfig(element)
# treat like list - we assume that if the first two tags
...