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Checking if a variable is not nil and not zero in ruby
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Use 'or' instead of ||
– Orion Edwards
Nov 2 '08 at 4:57
94
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How can I declare and use Boolean variables in a shell script?
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Revised Answer (Feb 12, 2014)
the_world_is_flat=true
# ...do something interesting...
if [ "$the_world_is_flat" = true ] ; then
echo 'Be careful not to fall off!'
fi
Original Answer
Caveats: https://stackoverflow.com/a/21210966/89391
the_world_is_fla...
What is the difference between a URI, a URL and a URN?
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From RFC 3986:
A URI can be further classified as a locator, a name, or both. The
term "Uniform Resource Locator" (URL) refers to the subset of URIs
that, in addition to identifying a resource, provide a means of
locating the resource by describing its primary acces...
Is it safe to check floating point values for equality to 0?
I know you can't rely on equality between double or decimal type values normally, but I'm wondering if 0 is a special case.
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Using try vs if in python
Is there a rationale to decide which one of try or if constructs to use, when testing variable to have a value?
9 Ans...
Transitions on the CSS display property
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You can concatenate two transitions or more, and visibility is what comes handy this time.
div {
border: 1px solid #eee;
}
div > ul {
visibility: hidden;
opacity: 0;
transition: visibility 0s, opacity 0.5s linear;
}
div:hover > ul {
...
Various ways to remove local Git changes
I just cloned a git repository and checked out a branch. I worked on it, and then decided to remove all my local changes, as I wanted the original copy.
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When do I really need to use atomic instead of bool? [duplicate]
...nstructions that are emitted to manipulate an std::atomic<bool> may (or may not) be the same as those for an ordinary bool, but being atomic is a larger concept with wider ramifications (e.g. restrictions on compiler re-ordering). Furthermore, some operations (like negation) are overloaded on ...
Understanding checked vs unchecked exceptions in Java
...e say that checked exceptions (i.e. these that you should explicitly catch or rethrow) should not be used at all. They were eliminated in C# for example, and most languages don't have them. So you can always throw a subclass of RuntimeException (unchecked exception)
However, I think checked excepti...
What is JavaScript's highest integer value that a number can go to without losing precision?
...integral value of this type is Number.MAX_SAFE_INTEGER, which is:
253-1, or
+/- 9,007,199,254,740,991, or
nine quadrillion seven trillion one hundred ninety-nine billion two hundred fifty-four million seven hundred forty thousand nine hundred ninety-one
To put this in perspective: one quadrill...