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detach all packages while working in R
...*) is not necessary but can be useful to prevent the NULL reply from vertically spamming the R window.
(edit: 9/20/2019) In version 3.6.1
It may be helpful to convert loaded only names(sessionInfo()$loadedOnly) to explicitly attached packages first, and then detach the packages, as so.
lapply(names(...
What is a clean, pythonic way to have multiple constructors in Python?
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Actually None is much better for "magic" values:
class Cheese():
def __init__(self, num_holes = None):
if num_holes is None:
...
Now if you want complete freedom of adding more parameters:
class Cheese...
What is the purpose of class methods?
...sson was that Python is not Java , and so I've just spent a while turning all my Class methods into functions.
17 Answers
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How many concurrent AJAX (XmlHttpRequest) requests are allowed in popular browsers?
... No, the limits are imposed on the domain. So you could technically get FF up to 12 connections if you had a subdomain in addition to your site.
– Bob
Feb 18 '09 at 13:39
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Can I create links with 'target=“_blank”' in Markdown?
...rget="_blank">Hello, world!</a>
Most Markdown engines I've seen allow plain old HTML, just for situations like this where a generic text markup system just won't cut it. (The StackOverflow engine, for example.) They then run the entire output through an HTML whitelist filter, regardless, ...
Immutability of Strings in Java
...t, and changing a reference. s2 still points to the same object as we initially set s1 to point to. Setting s1 to "Help!" only changes the reference, while the String object it originally referred to remains unchanged.
If strings were mutable, we could do something like this:
String s1 = "Hello";
St...
Extract traceback info from an exception object
...ion("foo occurred").with_traceback(tracebackobj)
These features are minimally described as part of the raise documentation.
All credit for this part of the answer should go to Vyctor, who first posted this information. I'm including it here only because this answer is stuck at the top, and Python...
Difference between abstract class and interface in Python
... @L.DeLeo - are you sure your notion of has-a vs. is-a is correct? I generally view the distinction as has-a = member variable vs. is-a = inheritance (parent class or interface). Think Comparable or List in Java; those are is-a relationships, regardless of whether they're interfaces or abstract cl...
How to remove k__BackingField from json when Deserialize
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Automatic Property syntax is actually not recommended if the class can be used in serialization. Reason being the backing field is generated by compiler which can be different each time code is compiled. This can cause incompatibility issues even if no chang...
How to implement an STL-style iterator and avoid common pitfalls?
...requirements for an iterator to be "STL-style" and what are some other pitfalls to avoid (if any)?
8 Answers
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