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Getting the object's property name
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More specifically, Object.keys(obj) returns an array of property names, i.e. keys, belonging to the passed in obj.
– a learner has no name
Mar 26 '16 at 12:43
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How much is the overhead of smart pointers compared to normal pointers in C++?
..._ptr always has memory overhead for reference counter, though it is very small.
std::unique_ptr has time overhead only during constructor (if it has to copy the provided deleter and/or null-initialize the pointer) and during destructor (to destroy the owned object).
std::shared_ptr has time overhe...
Print variables in hexadecimal or decimal format
... brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 4...
PHP Sort Array By SubArray Value
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That doesn't really helpe me as usort requires I provide it a function to use - which is the difficult bit I can't get my head round
– Sjwdavies
Mar 19 '10 at 13:15
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How do you read CSS rule values with JavaScript?
I would like to return a string with all of the contents of a CSS rule, like the format you'd see in an inline style. I'd like to be able to do this without knowing what is contained in a particular rule, so I can't just pull them out by style name (like .style.width etc.)
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Why do we need the “event” keyword while defining events?
...-like events and public fields of delegate types look similar, but are actually very different.
An event is fundamentally like a property - it's a pair of add/remove methods (instead of the get/set of a property). When you declare a field-like event (i.e. one where you don't specify the add/remove ...
IntelliJ and Tomcat…changed files are not automatically recognized by Tomcat
...r "Update resources" or "Update Classes and Resources"
Update resources: All changed resources (that is, all application components other than the classes) will be updated.
Update classes and resources: All changed resources will be updated; changed classes will be recompiled. Note that whether th...
Only read selected columns
...g","Sep","Oct","Nov","Dec"))
dat <- fread("data.txt", drop = c(8:13))
All result in:
> data
Year Jan Feb Mar Apr May Jun
1 2009 -41 -27 -25 -31 -31 -39
2 2010 -41 -27 -25 -31 -31 -39
3 2011 -21 -27 -2 -6 -10 -32
UPDATE: When you don't want fread to return a data.table, use the data.ta...
SVN+SSH, not having to do ssh-add every time? (Mac OS)
...e, I edited the ~/.ssh/config file (you may have to create it) to point to all the keys I have. Mine has the following:
IdentityFile ~/.ssh/identity
IdentityFile ~/.ssh/id_rsa
IdentityFile ~/.ssh/id_dsa
IdentityFile ~/.ssh/my_other_identity_here
IdentityFile ~/.ssh/yet_another_identity_here
Acco...
Take the content of a list and append it to another list
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Take a look at itertools.chain for a fast way to treat many small lists as a single big list (or at least as a single big iterable) without copying the smaller lists:
>>> import itertools
>>> p = ['a', 'b', 'c']
>>> q = ['d', 'e', 'f']
>>> r = ['g', ...