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HashSet versus Dictionary w.r.t searching time to find if an item exists
...s for Dictionary is so fast that there is no benefit from using HashSet at all, in the OP's case.
– EtherDragon
Jul 27 '12 at 23:03
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How can I declare and define multiple variables in one line using C++?
I always though that if I declare these three variables that they will all have the value 0
10 Answers
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Why is Scala's immutable Set not covariant in its type?
...ameter of type A due to the contravariance of functions. Set could potentially be contravariant in A, but this too causes issues when you want to do things like this:
def elements: Iterable[A]
In short, the best solution is to keep things invariant, even for the immutable data structure. You'll...
pydot and graphviz error: Couldn't import dot_parser, loading of dot files will not be possible
...workX (e.g. this NetworkX example failed). I kept getting: global name 'dot_parser' is not defined. Your solution solved this problem.
– qtips
Aug 6 '13 at 0:41
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JavaScript, elegant way to check nested object properties for null/undefined [duplicate]
...e of using the app this gets populated. Let's say somwhere, after an AJAX call or something i do this:
4 Answers
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MySQL Orderby a number, Nulls last
... tablename WHERE visible=1 ORDER BY -position DESC, id DESC
It is essentially the inverse of position DESC placing the NULL values last but otherwise the same as position ASC.
A good reference is here http://troels.arvin.dk/db/rdbms#select-order_by
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Profiling Vim startup time
... if you want it to just print it, try vim --startuptime /dev/stdout +qall
– Capi Etheriel
Jan 15 '13 at 17:37
1
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Glorified classes in the Java language
... lot of different answers, so I thought it would be useful to collect them all (and add some):
Classes
AutoBoxing classes - the compiler only allows for specific classes
Class - has its own literals (int.class for instance). I would also add its generic typing without creating new instances.
Stri...
Validating email addresses using jQuery and regex
...EmailAddress(emailAddress) {
var pattern = /^([a-z\d!#$%&'*+\-\/=?^_`{|}~\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]+(\.[a-z\d!#$%&'*+\-\/=?^_`{|}~\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]+)*|"((([ \t]*\r\n)?[ \t]+)?([\x01-\x08\x0b\x0c\x0e-\x1f\x7f\x21\x23-\x5b\x5d-\x7e\u00A0-\uD7FF\uF900-\u...
What is a lambda (function)?
...us and refers to anonymous functions in programming.
Why is this cool? It allows you to write quick throw away functions without naming them. It also provides a nice way to write closures. With that power you can do things like this.
Python
def adder(x):
return lambda y: x + y
add5 = adder(5)...