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What's the difference between returning void and returning a Task?
...arious C# Async CTP samples I see some async functions that return void , and others that return the non-generic Task . I can see why returning a Task<MyType> is useful to return data to the caller when the async operation completes, but the functions that I've seen that have a return typ...
What does the “Just” syntax mean in Haskell?
...d does. Every Haskell tutorial that I have looked at just starts using it randomly and never explains what it does (and I've looked at many).
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C++ auto keyword. Why is it magic?
...ose. But just recently, I encountered code that used it as a type name in and of itself. Out of curiosity I tried it, and it assumes the type of whatever I happen to assign to it!
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Concatenate a vector of strings/character
...:
stri_paste(letters, collapse='')
## [1] "abcdefghijklmnopqrstuvwxyz"
And some benchmarks:
require(microbenchmark)
test <- stri_rand_lipsum(100)
microbenchmark(stri_paste(test, collapse=''), paste(test,collapse=''), do.call(paste, c(as.list(test), sep="")))
Unit: microseconds
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Can dplyr package be used for conditional mutating?
... TRUE ~ NA_real_))
Added - arithmetic/na_if If the values are numeric and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using...
How do HTML parses work if they're not using regexp?
...s every day asking how to parse or extract something from some HTML string and the first answer/comment is always "Don't use RegEx to parse HTML, lest you feel the wrath!" (that last part is sometimes omitted).
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Does Java casting introduce overhead? Why?
...t objects of one type to another? Or the compiler just resolves everything and there is no cost at run time?
5 Answers
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Local variables in nested functions
..., I know it's going to look horribly convoluted, but please help me understand what's happening.
4 Answers
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Django: “projects” vs “apps”
... ready to build using Django. I'm going to avoid using the terms "project" and "application" in this context, because I'm not clear on their specific meaning in Django.
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Convert.ChangeType() fails on Nullable Types
...s not seem to work for uniqueidentifier to string.
– Anders Lindén
Nov 5 '18 at 10:32
Is there any particular reason ...