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Scala: Abstract types vs generics
I was reading A Tour of Scala: Abstract Types . When is it better to use abstract types?
4 Answers
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Split delimited strings in a column and insert as new rows [duplicate]
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Here is another way of doing it..
df <- read.table(textConnection("1|a,b,c\n2|a,c\n3|b,d\n4|e,f"), header = F, sep = "|", stringsAsFactors = F)
df
## V1 V2
## 1 1 a,b,c
## 2 2 a,c
## 3 3 b,d
## 4 4 e,f
s <- strsplit(df$V2, split = ",")
data.frame(V1 = ...
Laravel 4 Eloquent Query Using WHERE with OR AND OR?
How do I say WHERE (a = 1 OR b =1 ) AND (c = 1 OR d = 1)
11 Answers
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Should I return a Collection or a Stream?
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The answer is, as always, "it depends". It depends on how big the returned collection will be. It depends on whether the result changes over time, and how important consistency of the returned result is. And it depends very much on how the user is likely to use the answer.
First, no...
Does Java support default parameter values?
... complicated. For other methods, renaming some cases or using a parameter object can help. This is when you have enough complexity that differentiating is difficult. A definite case is where you have to differentiate using the order of parameters, not just number and type.
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How to check command line parameter in “.bat” file?
My OS is Windows Vista. I need to have a ".bat" file where I need to check if user enters any command-line parameter or not. If does then if the parameter equals to -b then I will do something otherwise I will flag "Invalid input". If user does not enter any command-line parameter then I will d...
Multiple variables in a 'with' statement?
Is it possible to declare more than one variable using a with statement in Python?
6 Answers
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What is the difference between a deep copy and a shallow copy?
What is the difference between a deep copy and a shallow copy?
31 Answers
31
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How do I compare two hashes?
I am trying to compare two Ruby Hashes using the following code:
14 Answers
14
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How do you get the logical xor of two variables in Python?
How do you get the logical xor of two variables in Python?
24 Answers
24
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