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Default function arguments in Rust
...you can get a similar behavior using Option<T>
fn add(a: Option<i32>, b: Option<i32>) -> i32 {
a.unwrap_or(1) + b.unwrap_or(2)
}
This accomplishes the objective of having the default value and the function coded only once (instead of in every call), but is of course a who...
best way to get the key of a key/value javascript object
...
If you want to get all keys, ECMAScript 5 introduced Object.keys. This is only supported by newer browsers but the MDC documentation provides an alternative implementation (which also uses for...in btw):
if(!Object.keys) Object.keys = function...
How do I break a string over multiple lines?
...se "..." if you need to split lines in the middle of words or want to literally type linebreaks as \n:
key: "Antidisestab\
lishmentarianism.\n\nGet on it."
YAML is crazy.
Block scalar styles (>, |)
These allow characters such as \ and " without escaping, and add a new line (\n) to the end o...
Difference between filter and filter_by in SQLAlchemy
... filter on users.id. Instead, it will evaluate id == id as True and return all users. You need to use .filter(users.id == id) (as demoed above). I made this mistake earlier today.
– Nico Cernek
Feb 22 '19 at 23:00
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Scala list concatenation, ::: vs ++
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325
Legacy. List was originally defined to be functional-languages-looking:
1 :: 2 :: Nil // a li...
Calculate the median of a billion numbers
...bably too late if this had been an interview, but never mind:
Machine 1 shall be called the "control machine", and for the sake of argument either it starts with all the data, and sends it in equal parcels to the other 99 machines, or else the data starts evenly distributed between the machines, an...
What is the most efficient way of finding all the factors of a number in Python?
Can someone explain to me an efficient way of finding all the factors of a number in Python (2.7)?
22 Answers
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Entity Framework: One Database, Multiple DbContexts. Is this a bad idea? [closed]
...y single context in your application can do that. The trick for this is usually one additional context containing all your entities which is used only for database creation. Your real application contexts containing only subsets of your entities must have database initializer set to null.
There are...
FFmpeg: How to split video efficiently?
I wish to split a large avi video into two smaller consecutive videos. I am using ffmpeg.
9 Answers
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When to use the brace-enclosed initializer?
...py (=) initialization (because then in case of error, you'll never accidentally invoke an explicit constructor, which generally interprets the provided value differently). In places where copy initialization is not available, see if brace initialization has the correct semantics, and if so, use that...