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Is it safe to ignore the possibility of SHA collisions in practice?
... on Earth within the next second, obliterating civilization-as-we-know-it, and killing off a few billion people? It can be argued that any unlucky event with a probability lower than that is not actually very important.
If we have a "perfect" hash function with output size n, and we have p messages...
Flask vs webapp2 for Google App Engine
I'm starting new Google App Engine application and currently considering two frameworks: Flask and webapp2 . I'm rather satisfied with built-in webapp framework that I've used for my previous App Engine application, so I think webapp2 will be even better and I won't have any problems with it.
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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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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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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...
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 I unshelve to a different branch in tfs 2008?
...hat some developer in my team shelved his changes that he did in branch A. And I am working on branch B. Can I unshelve his changes into branch B? (By GUI or command prompt)
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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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