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Converting from a string to boolean in Python?
...ref.html#distutils.util.strtobool
True values are y, yes, t, true, on and 1; false values are n, no, f, false, off and 0. Raises ValueError if val is anything else.
Be aware that distutils.util.strtobool() returns integer representations and thus it needs to be wrapped with bool() to get Bool...
How to check if object has any properties in JavaScript?
...ws:
for(var prop in ad) {
if (ad.hasOwnProperty(prop)) {
// handle prop as required
}
}
It is important to use the hasOwnProperty() method, to determine whether the object has the specified property as a direct property, and not inherited from the object's prototype chain.
Edit
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What is /dev/null 2>&1?
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>> /dev/null redirects standard output (stdout) to /dev/null, which discards it.
(The >> seems sort of superfluous, since >> means append while > means truncate and write, and either appending to or writing to /dev/null has the same n...
Bash tool to get nth line from a file
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head and pipe with tail will be slow for a huge file. I would suggest sed like this:
sed 'NUMq;d' file
Where NUM is the number of the line you want to print; so, for example, sed '10q;d' file to print the 10th line of file.
Ex...
What are the differences between vector and list data types in R?
What are the main differences between vector and list data types in R? What are the advantages or disadvantages of using (or not) these two data types?
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Inline SVG in CSS
...rk nicely is Safari (5.1.4). In Opera 11.62 the gradient is black, in IE 9 and Firefox 12 it's white. In Chrome 19, it works UNLESS you specify the width/height of the SVG in % units. I'd say it's more of an oddity than a real feature. It's a cool find though.
– toniedzwiedz
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How to get active user's UserDetails
...ion (like the login or id) stored in the principal or
want to learn how a HandlerMethodArgumentResolver or WebArgumentResolver can solve this in an elegant way, or just want to an learn the background behind @AuthenticationPrincipal and AuthenticationPrincipalArgumentResolver (because it is based on...
How to store custom objects in NSUserDefaults
Alright, so I've been doing some poking around, and I realize my problem, but I don't know how to fix it. I have made a custom class to hold some data. I make objects for this class, and I need to them to last between sessions. Before I was putting all my information in NSUserDefaults , but this...
Difference between web reference and service reference?
What is the difference between web reference and service reference in WCF?
Which is preferable in WCF?
5 Answers
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Why is “if not someobj:” better than “if someobj == None:” in Python?
... the object has a __nonzero__ special method (as do numeric built-ins, int and float), it calls this method. It must either return a bool value which is then directly used, or an int value that is considered False if equal to zero.
Otherwise, if the object has a __len__ special method (as do contain...